Rebarrel from 223 to 204

[Sherlock]

Gbal, can those figure be relied upon? They show the 204 whups the 223 at middling speeds with 50% less drift and 25% less drop even before 204 trajectory is adjusted for a max of 1" above line of sight.

The general consensus here from those who have had both is the difference is negligible in the field, but your figures show the 204 does have a significant advantage.

 

 

I will answer that if I may. NO. the figures used most certainly can not be taken as fact.,,, actually quite the opposite

 

Even the bullet manufacturers "Sierra" qualify the stated BC of 0.287 at speeds above 3600 fps

So even if you average the inflated BC that Sierra use over - say 400 yrds - you end up with a BC of around 0.250

 

Sierra's figures

• 287 at 3600 fps and above
• .270 between 3600 and 3400 fps
• .255 between 3400 and 2800 fps
• .236 between 2800 and 2300 fps
• .210 between 2300 and 1900 fps

 

This is the whole point of the thread - on paper the 204 appears to kick the 223 into the weeds , therefore (IF TRUE) from a purely "ballistic POV" the 204 would be well worth considering about re-barreling a 223 into.

 

In reality it doesn't do any such thing .. the drop and drift are negligible when you compare Like with Like.

Simply plugging in bullet BC's which are known to be high, does NOT do shooting any favours - it just continues the BS.

.

These are expensive mistakes to make - and I can tell you. I wasn't a happy bunny when I spent over £700 on a re-barrel expecting to get a calibre that was head and shoulders above my 223. What I got was a rifle that was ballistically similar - but had lost the versatility of the 22 cal.. as Big Al put it - " A one trick Pony"

 

So by all means get it if it is an itch that needs a scratch - Sure it will knock fox and bunnies over for fun - no different than the 223. But in the real world - - If you want to step up in performance - you have to step up in case size and look at 22.250 and 22 BR or a 6 mm.

 

Last point regarding the reported velocity of the 204.. I crono'd mine ( 24 inch barrel) l with some factory rounds - it said ton the box to expect 3900 fps - they were doing just over 3600 fps - therefore my 223 was now actually flatter shooting ... its a pi55 take

 

Worth a look - make up your own minds.

 

https://www.youtube.com/watch?v=HHyGN1Gcfg0

 

 

https://www.youtube.com/watch?v=wQTKO1PN2PI

 

 

 

ATB

S

[snakeman]

I agree that there seems to be little difference between the 204 and 223 40gn loads when taking anecdotal evidence into account. I prefer to keep the trajectory up to an inch above sight line at most, and the heavy 69+gn 223 loads would have too much of a pronounced trajectory for foxing.

I appreciate that heavy 223 offers 'jack of all trades' versatility, which must be attractive for owner wanting it to do everything, but I have plenty of other kit for vermin deer etc, and am looking for the 'master' for foxing at 300 yards maximum.

To get significantly better fox lamping performance than 223 I would have to step up to a larger case such as 22/250, 22BR etc.

 

"master for foxing at 300yds max"? ...if that's the quest most, if not all, cals mentioned in this thread will be any fox's 'master', apart from the r/f.

 

As previously mentioned in post #13 though, I don't think you'll better the 8/9 twist .223 for its superb versatility and good barrel life, given the care taken on the loads.

 

For foxing however I have always chosen the .243 - personal preference and due to the significantly lower round count that goes down my.243 tube, I have no concerns about barrel life. It is used solely as my foxing rig, with no range work apart from an unfussy and infrequent zeroing.

 

But of course, we are talking here of probably two of the most popular and extensively used cartridges the world of fox-shooting has known - take your pick.

 

I would not hesitate to use any of the calibres mentioned on fox but, would not consider a shot over 300yds, even in daytime with any calibre, and as for when darkness has fallen, forget it even at 200yds - but that's me. I feel the margin for error as distance increases, likewise increases. Think backstops; ricochets; think wind and gusts; think livestock; think boundaries; think confidence in your own ability, and most of all think of the animal, and a humane kill that's certain (if you can) before taking your shot.

[75sako]

I don't think the 20 cal figures stand up to their claims.Two friends have 204 and 223 rifles . We chrono'd them both and the 204 was well down on velocity

[Guesty]

Right, we are all settled then that 204 is not significantly better than 223, which means that the quoted manufacturers stats must be incorrect.

I have shot foxes out to 300 yards under the lamp with a 22/250, though that is rather longer than the usual range. Had I been using my 223 I would not have attempted shots at that distance. I was hoping that 204 might have given the extra legs, but it seems not.

[VarmLR]

 

...

[VarmLR]

...

[VarmLR]

....triple post

[VarmLR]

...

[VarmLR]

 

 

I will answer that if I may. NO. the figures used most certainly can not be taken as fact.,,, actually quite the opposite

 

Even the bullet manufacturers "Sierra" qualify the stated BC of 0.287 at speeds above 3600 fps

So even if you average the inflated BC that Sierra use over - say 400 yrds - you end up with a BC of around 0.250

 

Sierra's figures

• 287 at 3600 fps and above
• .270 between 3600 and 3400 fps
• .255 between 3400 and 2800 fps
• .236 between 2800 and 2300 fps
• .210 between 2300 and 1900 fps

 

This is the whole point of the thread - on paper the 204 appears to kick the 223 into the weeds , therefore (IF TRUE) from a purely "ballistic POV" the 204 would be well worth considering about re-barreling a 223 into.

 

In reality it doesn't do any such thing .. the drop and drift are negligible when you compare Like with Like.

Simply plugging in bullet BC's which are known to be high, does NOT do shooting any favours - it just continues the BS.

.

These are expensive mistakes to make - and I can tell you. I wasn't a happy bunny when I spent over £700 on a re-barrel expecting to get a calibre that was head and shoulders above my 223. What I got was a rifle that was ballistically similar - but had lost the versatility of the 22 cal.. as Big Al put it - " A one trick Pony"

 

So by all means get it if it is an itch that needs a scratch - Sure it will knock fox and bunnies over for fun - no different than the 223. But in the real world - - If you want to step up in performance - you have to step up in case size and look at 22.250 and 22 BR or a 6 mm.

 

Last point regarding the reported velocity of the 204.. I crono'd mine ( 24 inch barrel) l with some factory rounds - it said ton the box to expect 3900 fps - they were doing just over 3600 fps - therefore my 223 was now actually flatter shooting ... its a pi55 take

 

Worth a look - make up your own minds.

 

https://www.youtube.com/watch?v=HHyGN1Gcfg0

 

 

https://www.youtube.com/watch?v=wQTKO1PN2PI

 

 

 

ATB

S

 

 

APOLOGIES FOR MULTIPLE POSTS....NO IDEA HOW THAT HAPPENED!!!

 

+1 with large dangley bells on

 

Very salient observations.

 

I've had this conversation with so many people now. Last year, I visited a chap who was concerned that he'd not the the performance from the 223, and wanted the 204 because all his foxing mates had them. I brought the chrono with me, and demonstrated that the 223 without loading too hot, was capable of real world comparative performance. I had several loads, and could only demo the 50gr upwards as 40's won't shoot in my latest barrelled 223 which is 1/8, but they did ion my previous slower twist barrel. I fired a few 60gr Vmax through which I'd loaded up a bit from my standard load (3150fps) but still safe loads, and they were zipping out at over 3200fps, and the 50gr at well over that. 40gr in the slower twist could be loaded easily for real world 3600 fps or greater, so to a few hundred yards there was actually nothing in it at all between the 204 or 223.

 

 

Personally, if I wanted "flatter" then something like a 22BR with a 40gr Sierra Blitzking loaded for 4100 fps is probably about as good as it gets trajectory-wise but even then, there's always going to be some drop to compensate for if zero is 200 yards and POI is 300 yards and also wind cannot be ignored at those distances. Get one evening and say a 10 to 15mph wind, and even with a 22BR it'll not be point and shoot, but point and hold off a little.

[gbal]

To clarify/answer some of the points raised: all the data are from Forker Ammo and Ballistics 4th ed-for commercial ammo.

IT's all SAAMI,and same barrel length;it is possible home loading can't duplicate factory claims (it's happened before-powder used not available).

I did say BC varied a little-the data includes several manufacturers using different bullets,Nosler,Sierra,Hornady etc.Since MVs and bullets vary,I didn't include the detail. For the 40g 204 the BC given were around .25 +/_ .2;and for the 40g 223 around .221 +/_ .1

Gets messy-with several co-variables,but the point is that it does not actually have much effect,esp out to 240yish-BC has a small effect then to 300-but not much....looking again ,it's about 1"drop,and 2"drift more at 300 for the hi/lo BC figures in 40g calibres.

 

From the figures for drop Forker gives, the 300y drop for 204 is about 4.3 inches and for 223 it's about 5.5...so thats about an inch;and for wind it's about 8 inches and 12 inches drift....

 

Which is why my last para says " NOTHING IN IT TO 230/240y"

 

Can't see that as kicking anything into touch- or similar interpretations....and I included 243 and 22/250 examples to emphasise the step up that comes from larger capacity cases-and better BCs.

Though I did not say so,it is ever likely that similar capacity cases won't differ with the same weight bullet very much,though velocity and BC (yes it varies within and between,as I've said for years here) will have relatively minor effects,at distances out to 250,maybe 300y.....which seems to be confirmed.

 

"EVERYONE IS PARTLY RIGHT" (quote) also indicates there can be a bit of cherry picking of the data,but it won't be very convincing.If 204 fails to deliver velocities as claimed,then it will do a little poorer-if 223 is up to spec. Home releoading brings in so many uncertainties,we sometimes get disagreements ( chronos just vary)..hence the SAAMI specs....but to repeat,for the hard of reading ( :-):

 

"There is nothing in it to 240y".

 

( and not much to 300,esp for drop).

 

Seems to be where most experience ends up too. There is always some variation,especially when several bullets,powders,rifles and MV estimates and often small samples are used (understandably).

I don't see anything in the published data to rock the 'pretty similar boats-choose either" summary,for this use.The 223 can be considerably more versatile-if that means a 'bit further with better BC bullets'-undoubtedly (with the right twists/BC bullets,a LOT further.-though I don't doubt a tin can can be hit with a 204 at 900yards ,but even less reliably that wih a 223).

 

Even at its published best,there isn't much in it,and if the 204 can't quite produce those Mvs,it will lose any slight edge-so that:

 

"There is nothing in it to 240y"....and even less difference to 300y that with the published data (which is small).

 

I'd have thought a closer look at the published data would have avoided disappointments-the 204has advantages,but super ballistic supremacy over 223 at foxing ranges,is NOT one of them.One good reason to add that kind of data to anecdote or casual recommendation,esp as it will give longer range data too.

 

And yes, i've been down the same road with the 222/17rem with almost exactly the same outcome-ballistic clones as 250y+bunny rifles (BC,MV and maybe accuracy,pretty well evened out). I came to prefer the 17r for other reasons,but only for bunnies,but really,nothing in it! (Not sure BC had been touted back then,but would be in the mix).

Good shooting whatever your choices.

gbal

[Alycidon]

To find a significant benefit in a 20 cal over a 223 then you do have to use heavier 20 cal bullets from a bigger case, even then under 300 yards difference is minimal Both calibers will get the job done OK as you know,. While drops can just be dialled out given a known range drifts are far more difficult and its usually drifts where we come unstuck unless given time to range and dial. But if its way out in the distance and you have 3 seconds to find it and shoot then the 20 is somewhat easier as drops and drifts are somewhat lower given same bullet weights..

 

My friend uses 22BR with 55gr (?) Blitzkings , I use 20BR usually with 39gr SBKs or 50gr Bergers, while we have never run them side by side at say 450 yards I would be quite happy to use his and I think he would be happy to use the 20 under a lamp. I do feel that the larger frontal area of the 22 does cause a bigger wound channel. Many foxes taken with the 20BR usually with 39gr SBK or 50gr Bergers have minimal carcase damage although they do drop just the same.

 

A

[VarmLR]

I tried the 223 today, just out of interest, at around 420 yards, close on 1/4 mile. The target was a 3 inch wide stone on a steep muddy bank. Wind was light, left to right possible 4mph. Having already set the Leica RF's ballistic app to the "US5" setting for 100 yd zero (this very closely matches the actual trajectory to about 500 yards for my 69gr load), it was simply point the RF at the bank that the stone was on, and it gave 32 clicks (8.5moa) up. I dialled in the solution plus 1.5moa left to account for the slight breeze and for about an inch spin-drift on the 69gr TMK. Squeezed the trigger and stone vanishes a second later. Had that been a fox trotting slowly across my sight, I reckon it would have been picked off inside of 15 seconds, as once the rangefinder got the distance and elevation needed, it took literally a few seconds to dial the solution needed.

 

I tested at 300 and 200 yards respectively and was getting about 13.5 inches drop at 300 yards and almost exactly 3.5 inches at 200, meaning that in today's balmy weather the 69gr pills were probably doing around 2820fps. My rifle is zeroed for 100 yards though. On a fox, I'd be more than happy to point and shoot with that zero to 200, with just a little holdover. Checked my load data when I got home and found that the load had been worked up in colder weather and tested at 2800fps.

[gbal]

69g @ 3000 BC .336 0 7.4

@ 2950 BC .300 0 8.1

@ 2850 BC .338 0 8.3

@ 2850 BC .338. 0. 8.3

@ 2735 BC .313 0 9.5

 

Drops at 200 and 300 for Remington (HP) ,Federal (SMK),Nosler(CC) Black Hills(SMK),and Focchi(MK) SAAMI ammo.

Compare all this data to:

 

69g TMK @ 2800+ (probably) BC . 100y. 0. 200 3.5. 300 13.5 (about) and 1.5 windage+,which is 6.3 inches

 

Different zero makes it difficult to eyeball,and the TMK data isn't too secure,but accept as close ball park.(a three inch stone allows 1.5 +\- tolerance for a hit,too-but thats at 420 yards.Good shot.SAAMI data windage 420y,4mph wind averages 7.5 inches ie

 

Maybe someone can be bothered to see if the majors manufacturers have a credibility problem.

Doesn't look eyeball much to me wih slightly rose tints on..(windage diff is just 1.2 with wide MV/BC averaged for SAAMI,MV and maybe drop for field data is not neccessarily exact,and an all round tolerance of 1.5 inches in the hit target.)

Note the BC and MV changes don't here impact much to 300y,though some may well be 'cancelling out",and all this just reinforces the consensus that there isn't much in it.But not that Forker speak with forked tongue!

BUT: The BC figures do look quite high,though the original comparisons of 223 and 204 should hold comparatively-as the 204BCs are equally likely to be high,though the bullet weight was 40g with BC around low .2s. AND-neither BC nor MV has a large effect on drop to 250 ish (given they are cartridge average). Still,this BC issue does recur....What we do not have is SAAMI data,under good controlled conditions,with Litz BCs (G1) and field data with such good control data. Little wonder if there are discrepancies (good MVs would help too-all magneto/Lab radar would eliminate much mischief. AS the great Warren Page said,vis a vis 'ballistic' claims. "It's differnces of opinion that make for horse races"-well,races are funas are pre race discussions-but we should be able to measure better now-and they (R,W,N etc) should too! Too many..... err... 'nag-ging doubts?

 

It is good to have real field data. As ever,guidlines can be good,but know your own rifle,and input the best possible measured data you can-that's what your ballistic solution engine will use.It can't compensate any input errors (cf 10 mph wind means a 20 inch wind drift-a 10% error would mean a missed stone,without any other factors).

 

gbal

[VarmLR]

First off, apologies to Guesty for the thread drift as this ought really to be in the handloading section as part of load dev and testing, but it serves a purpose I guess, placed here too.

 

Interestingly George, I've just input the field test data into Strelock and into the Litz calculator using the Litz derived G7 BC and my own rudimentary tests today, if anything, show the Litz data as slightly pessimistic. Mine work out close to 0.19 G7 compared with the Litz 0.182, and would appear to re-affirm Sierra's own G1, when using that (ok....very slightly lower than their G1) so, within a few percent of Sierra's data on one side and within about 4% of Litz data on the other. I'm happy with the tests, as I did repeat them at different ranges and work back in conditions about as favourable as I'm likely to encounter. The only thing was the target size which as you point out, could have masked actual drops at the extreme 420 by +/- 1.5 inches, hence that few percent variance in calculated BC could easily swing more precisely to Litz or to Sierra.

 

Whatever the outcome, it is a useful exercise to do and I really need to re-do it out to 750 yards under tighter control. I have the opportunity next month of some 660 yd range work, so will use that and see how it correlates with current predictions. The idea is to use the DOPE and come up with a very reliable drop chart for that particular load and for the 77 load which I hope to shoot to 800 yards.

 

As Alycidon points out, whilst it's relatively easy to sort DOPE for the drops and compensate by holdover or dialling, it is less straightforward for wind, and once past 300 yards, if shooting small vermin, such as grounded squirrels, crows etc, today taught me that slight as it may be, spindrift also has to be taken into account on small targets where precision is important. I know that my rifle is 0.25 capable as I've repeated multipleshot groups at that many times with it, so an inch at 400 yards is what it ought theoretically be capable of, and spindrift at that range adds about another inch....the two = the difference between a miss or a not on small quarry. Hmmm......I wonder how many of those You tube videos are very selective in purported 600yd first time hits on small furry animals and birds!? Looked at in light of the above, a bit of luck along with no small amount of judgement and skill are involved! (we also seldom get to see the misses of which I'm willing to bet there's more of.....).

[minkstone]

I will answer that if I may. NO. the figures used most certainly can not be taken as fact.,,, actually quite the opposite

 

Even the bullet manufacturers "Sierra" qualify the stated BC of 0.287 at speeds above 3600 fps

So even if you average the inflated BC that Sierra use over - say 400 yrds - you end up with a BC of around 0.250

 

Sierra's figures

• 287 at 3600 fps and above
• .270 between 3600 and 3400 fps
• .255 between 3400 and 2800 fps
• .236 between 2800 and 2300 fps
• .210 between 2300 and 1900 fps

This is the whole point of the thread - on paper the 204 appears to kick the 223 into the weeds , therefore (IF TRUE) from a purely "ballistic POV" the 204 would be well worth considering about re-barreling a 223 into.

 

In reality it doesn't do any such thing .. the drop and drift are negligible when you compare Like with Like.

Simply plugging in bullet BC's which are known to be high, does NOT do shooting any favours - it just continues the BS.

.

These are expensive mistakes to make - and I can tell you. I wasn't a happy bunny when I spent over £700 on a re-barrel expecting to get a calibre that was head and shoulders above my 223. What I got was a rifle that was ballistically similar - but had lost the versatility of the 22 cal.. as Big Al put it - " A one trick Pony"

 

So by all means get it if it is an itch that needs a scratch - Sure it will knock fox and bunnies over for fun - no different than the 223. But in the real world - - If you want to step up in performance - you have to step up in case size and look at 22.250 and 22 BR or a 6 mm.

 

Last point regarding the reported velocity of the 204.. I crono'd mine ( 24 inch barrel) l with some factory rounds - it said ton the box to expect 3900 fps - they were doing just over 3600 fps - therefore my 223 was now actually flatter shooting ... its a pi55 take

 

Worth a look - make up your own minds.

 

https://www.youtube.com/watch?v=HHyGN1Gcfg0

 

 

https://www.youtube.com/watch?v=wQTKO1PN2PI

 

 

 

ATB

 

 

Amen!!......thankyou for that....as I've always said "real time shooting" not "quoted" BS

[22cf]

I will answer that if I may. NO. the figures used most certainly can not be taken as fact.,,, actually quite the opposite

 

Even the bullet manufacturers "Sierra" qualify the stated BC of 0.287 at speeds above 3600 fps

So even if you average the inflated BC that Sierra use over - say 400 yrds - you end up with a BC of around 0.250

 

Sierra's figures

• 287 at 3600 fps and above
• .270 between 3600 and 3400 fps
• .255 between 3400 and 2800 fps
• .236 between 2800 and 2300 fps
• .210 between 2300 and 1900 fps

This is the whole point of the thread - on paper the 204 appears to kick the 223 into the weeds , therefore (IF TRUE) from a purely "ballistic POV" the 204 would be well worth considering about re-barreling a 223 into.

 

In reality it doesn't do any such thing .. the drop and drift are negligible when you compare Like with Like.

Simply plugging in bullet BC's which are known to be high, does NOT do shooting any favours - it just continues the BS.

.

These are expensive mistakes to make - and I can tell you. I wasn't a happy bunny when I spent over £700 on a re-barrel expecting to get a calibre that was head and shoulders above my 223. What I got was a rifle that was ballistically similar - but had lost the versatility of the 22 cal.. as Big Al put it - " A one trick Pony"

 

So by all means get it if it is an itch that needs a scratch - Sure it will knock fox and bunnies over for fun - no different than the 223. But in the real world - - If you want to step up in performance - you have to step up in case size and look at 22.250 and 22 BR or a 6 mm.

 

Last point regarding the reported velocity of the 204.. I crono'd mine ( 24 inch barrel) l with some factory rounds - it said ton the box to expect 3900 fps - they were doing just over 3600 fps - therefore my 223 was now actually flatter shooting ... its a pi55 take

 

Worth a look - make up your own minds.

 

 

 

 

 

 

ATB

 

 

Amen!!......thankyou for that....as I've always said "real time shooting" not "quoted" BS

 

 

 

Im with Minkstone on this one, I have had a 20cal (20Prac) which had a 26" barrel, I was pushing the velocity as far as I dare with the primers as flat as a pancake. If I remember the velocity was 3650fps with the 39 grain Sierra Blitzkings. It was an incredibly accurate rifle which could consistently generate 0.25" groups and regularly took crows and pigeons out to 400yds.

 

However, was it any better than my .223rem Super Varmint pushing a 53 grain V-Max ??? My first hand experiences say No. The 53 grain VMax was for practical hunting purposes was just as accurate and just as flat and the difference in clicks when calculating windage wasnt worth talking about.

 

The big advantage the .223 had over the 20cal was that it was Muntjac legal and gave me the option with the 8 twist barrel of shooting 40-77 grain bullets.

[gbal]

Guys,the consensus sems to be that there is no significant advantage with the 204 over the 223 with 40 g bullets to about 250/300y-

whether this is based on individual 'field' shooting tests,or manufacturers published data.

Note that it is not at all uncommon for handloaders to fail to replicate the highest velocities manufacturers claim-sometimes this is because the powders used differ,or other factors come in-eg testing temperatures etc (let alone barrel length etc etc.

But the shortfall between factory data and 'real data' (even if this isn't 'flawed') is likely to be true for 0-here-both sets of factory data-the published figures are high for BOTH calibres (tho maybe a bit higher for 204?)...the comparative basis still holds -just as it does for differnt ways BC measures-consistency of comparison reduces any differencesin conclusions.

204 has little advantage over 223,as stated above.However you look at it,filed or whatever people thing manufacturers data is derived from. The absolute MVs-and BCs-and therfore nominal drops may differ,between measuring systems,but not much within a system (factory OR homeload/filed).

That's why there is no disagreement on conclusions-204 and 223 are very close,here (204 don't shoot 77g,end of).

 

IT's not helped by bringing in other cartridges,or a somewhat cavalier interpretation-a 4 " drop v a 5 " drop could be seen as 25% worse...but 'significant"...let alone that the 4" 'whups' the 5". (This is at 400 yards,remember). It is ONE inch-even without 'correction/compensation" on the scope -that is a hit (on a fox)....or AOLQ.

 

Add in 'different rifles' -even if nominally 'the same' (they won't be),differnt test conditions (eg temperature) etc etc....

 

Just for interest,are we generally comparing home loads to factory claims ( and how many have actually shot enough factory ammo to check the claimed velocity (I'd expect factory to be mostly 'optimistic'-or homeloads to be 'pessimistic'-anyhow,factory tending to higher MV -as in 22cf's video (maybe by a fair bit....but what does 100fps translate to 'in the 400y field"....??..

....let's say,not a reason to change your calibre/cartridge.!!!

 

(Not to say we don't-17,222,223 side by side....not much field difference to 250/300y (bullet,BC and MV composite aggregates are quite close ) precision varies too-and if we are talking at the level of 1 inch more drop at 400y,that confounds comparable measurement.....just another 'factor' relevant to non identical final data!)

 

"Apples to Apples" and most overstatements become as 'dust to dust'. While some 'statistical' claims can deceive,generally the error is in using the wrong stats,and misinterpreting ( a differnce can be not significant,yet larger than a difference which is significant,in the statistical sense....but the statistical sense is NOT the everyday/everyfield meaning of the word ...which latter I take to mean something like 25% fewer rabbit for the pot (or,in old money,three rather than four-that might be 'significant' depending on how many mouths there are to feed.) :-)

 

I think we are all more or less on the same page here,if not quite the same line. (The chapter is "204v223" for (fox) shooting to 300y"-it's a damn close run thing-choice is 'personal' rather than 'ballistic'.) It's a very wet morning,better read than shoot, for data!

 

gbal

[VarmLR]

 

 

Im with Minkstone on this one, I have had a 20cal (20Prac) which had a 26" barrel, I was pushing the velocity as far as I dare with the primers as flat as a pancake. If I remember the velocity was 3650fps with the 39 grain Sierra Blitzkings. It was an incredibly accurate rifle which could consistently generate 0.25" groups and regularly took crows and pigeons out to 400yds.

 

However, was it any better than my .223rem Super Varmint pushing a 53 grain V-Max ??? My first hand experiences say No. The 53 grain VMax was for practical hunting purposes was just as accurate and just as flat and the difference in clicks when calculating windage wasnt worth talking about.

 

The big advantage the .223 had over the 20cal was that it was Muntjac legal and gave me the option with the 8 twist barrel of shooting 40-77 grain bullets.

 

 

Yes, I agree with this and my own experience shooting lighter bullets in 223 is the same. Even the exercise carried out yesterday with the 69gr pills demonstrates that it is very rapid and accurate over 420 yards. The 223 I currently shoot is one of the most accurate rifle's that I've owned, also .25 capable. I usually use the 55gr spbt's from Sierra (#1365) for small deer if using the 223, and the heavies I reserve for accurate LR vermin or target work.

 

Having said all of that, for a dedicated LR vermin rifle, it's horses for courses, and a better round lies in one of the 6mm or 6.5mm chamberings (variation now being processed!). I'll take accuracy over speed every day of the week.

[gbal]

Varm,yes...with a 2 inch crow,a precision rig of at least .25 is a minimum start...and very few will be better-including Bench Rest-though that will have a fair chance against multiple crows,5 at a time. But I'd not relly on pro rata grouping (more precisely,group size based on that) as other factors creep in with distance,negligible at 100y.

 

Anyhow,spin/gyroscopic drift is a nice touch. IT's pretty complex,even LItz baulks a bit at the math,but gives about 9 inches gyro at 1000y,and 2.5 Coreolis. JUst what that would be at 420 yards is hard to estimate,clearly (esp if spin speed-decreasing-and rifle twist matter....as well as N/S Glos and E/W orientation......! Some Ballistic calculatorys include Coreolis in their program,but no 'field' ones can cope with gyroscopic drift(s).

 

So how much field data has allowed for these (or indeed published data)? Clearly a really good Applied Ballistics program is needed for the Applemac,to help sort out these 'apples/oranges' fudges! :-)

 

22cf-Even if the claim "kicked into the weeds' was sustainable,the weeds cannot be higher than 1 inch at 400y ! :-)

 

I'm not buying a 20 on that off chance,having studied the published data,and user testimony that evidences equivalence;(and 50+ years of similar 'discussion' about 17,222,223 -add in 19,and .14....interesting yes,superior,no. Precision,accuracy,velocity and BC combine,and just differ among the contenders).The 20/22 BR class go up a good notch.

The 6PPC,and 6BR for more distance,give a real advantage -Varm's point-few are dispatched by a faster lighter missile going past them. :-)

 

gbal

[VarmLR]

The spin drift is an interesting one. I don't allow for coreolis unless shooting 1000+, simply because it's not significant enough to worry about compared to other factors, but I know that on a still day on my own 420 yard test range, averaging groups, carefully shot (ie taking the centre of a group) that when one does everything possible to eliminate things like cant (I use a bubble level plus targets usually have a grid on them to help align the ret) then spin drift does work out at just over an inch with 69TMKs at that speed. It will vary with each bullet length, barrel twist and MV combination but if taking corvids at 400 plus yards, it's the sort of stuff you have to preferably test for yourself although some ballistic apps do take it into account. It takes a lot of shooting practice/cost though! Groups need to be 5 to 10 shot averages imho.

[gbal]

Varm,indeed.....lots of painstaking testing-individual to that rifle/load,though some generality possible.

My real point is that it exists,but how many shooters actually factor it into claims,where differnces afe already quite small-as these 204/223 issues. Useful to have your data for 223 at 420 for 69TMK.

Just to add in another marker,a 6mm 80g @3000fps 1/12 twist at 300y,has a gyroscopic drify of .4",and horizontal Corelois of .13" (.43 total),AND a vertical Coreolis component of near 1/4 inch.

 

OK-who allows for vert Coreolis -and remembers its up .23 inch if shooting East,and down .23 if shooting West.

 

Yes it's only 1/4 inch,but all these add up...and with 2" crows,there isn't much tolerance by 400yards (and that assumes perfect wind,and shooting,and a 1/4 ma rig and shooter.....in the field.....hmmmm.But it also impacts on claims about drop/drift when the real differences are indeed small- four such mistakes worth are what separates 204/223 on most 'analyses'.

I think the SIg 2400 might. Be better thn most for small but real factors (and some super/trans/sub sonics...if one wants rocket science ...but it's way way beyond the decent field Strelok/similar in price too.

 

All this and MVs estimated from 500y drops from a 'measured' group of three shots.....in field conditions....or even with a chronic chrono....a one inch discrepancy should be no surprise,but hardly decisive,either way.

 

Whatever the cartridge,they do matter with small targets at distance,if you want one miss in ten,rather than one hit in ten.

Good testing!

G

[Elliott]

Well, I had to scratch the itch so I've ended up buying a CZ527 Varmint in 204 Ruger. Hope to have it next week. 

From the 25" barrel I should be able to reach 3,900fps using Sierra 39gr Blitz, which have a similar BC to my 53gr V-Max. 

The 53gr V-Max are travelling at 3,100 fps from the 20" barrel in my T3 Varmint, so I expect to see the 39gr Blitz pip them. 

I'm liking the thought of a light, flat shooting and very frangible bullet for longer range rabbit, crow and magpie control which makes up most of my shooting. 

Should be suitable for knocking the foxes over too. 

[VarmLR]

Nice little rifle and one of my favourite short/mini actions.  Don't know why more people aren't shooting the 527, other than it's not as fashionable as some of the blackticool tools.

You could equally have got a similar result by buying a shot-out 527 and re-barrelling in a longer .223 tight twist (L-W do a match contour in 26" for a shade over £400 for the blank), but as you started with a shorter barrel 223, I can see why you picked what you did.  I personally wouldn't swap out my 223 for a 204 as there's no advantage, but then again I have the benefit of a 26" barrel.

If you have access to a chrony Elliot, would you mind testing some 204 loads and report back?  It might add to the info available for anyone searching or reading this thread RE 204 V's 223. I'm happy to re-test my 223 tomorrow with 60 V-max (in freezing conditions!) and will post the velocities measured.

[Elliott]

Yeah no problem. In terms of the 60gr V-Max, I think the BC isn't as good as the 53gr version. 

My pal has a 204 Ruger in a Howa Varmint model using a 24" barrel. Using Vhit 130, he's comfortably managing over 3,900 fps using 39gr Blitz with five shot group of around 0.25"

Higher velocity seems to make more of available BC and I'm not sure I'm getting the best out of my 223 with my 53gr V-Max at a pedestrian speed of 3,100fps. A longer barrel would be better, but theres certainly an advantage of having a flatter, possibly more frangable bullet for varminting

[GT3_richy]

48 minutes ago, Elliott said:

My pal has a 204 Ruger in a Howa Varmint model using a 24" barrel. Using Vhit 130, he's comfortably managing over 3,900 fps using 39gr Blitz with five shot group of around 0.25"

How much N130 is he using? I have no idea how he's seeing 3900 with 39sbk's and a 24" tube.

The Sierra load data gives a highest velocity of around 3700 (10x/Varget) from a 26" barrel, Hornadys 40gr loads arent much more. QL guesses closer to 3600. I think the factory Superformance 40gr's which no one seems to be able to replicate the velocity of have 3900 on the box?

My 20" T3X manages around 3450-3500 measured with Magnetospeed and Labradar, I'd be genuinely interested to hear what charge weight it is.

FPS and BC-'issues' aside, I get why 20cals arent popular as demonstrated in this thread - but I still love mine, its so nice to shoot - I'm sure you will have a blast, dont expect much change from bunnies though ;p