243 powder

[ted105]

Given the 243 is meant to be a barrel burner ,if over loaded ??.

I need some more powder ,i use RS 52 (Not usual I know ) and vit N140.,both do 1/4 Moa.

Which is best for barrel life on max or near to max loads 70 gr bullets .

[banus02]

i use n140 at 38grs 70gr nosler b/t and rs 52 at 37grs 87gr vmax 20" tikka sv both accurate the rs52 will kill the barrel sooner! pressure signs at 40gr n140 case marks and stiff bolt at 39grs rs 52. lapua or ppu cases

[snakeman]

ted

I've put through just over 500rds of 70g SBK atop 46.5g of Ramshot Hunter - no decrease in accuracy (yet)... Although this too is a double-bass powder, and is not barrel friendly.....but then again, the .243 is not what I use to plink with to be concerned about barrel-life - it's used solely for hunting

I use Hunter also with 85g Gamekings with excellent results. I'd go as far to say I'm more than pleased with the results and wouldn't change this powder for anything else, as it's the only powder that gave me consistent and stable accuracy out of a T3 lite.

BUT, as I said, rifle is used solely for fox control....I wouldn't even consider using .243 cartridge as a range rifle, but each to their own

ATB

[Laurie]

All ball type powders are double-based (nitroglycerin in the base-mix is an essential ingredient in getting the little balls to form in a 'distillation'' / precipitation process).

Despite that US Army studies have shown no reduction in military rifle barrel life between those used with single-based extruded powders and those with ball types. (All standard US military ball ammunition have been designed to use WCC produced ball powders from the St. Marks Powder Co, plant  in Florida since the 7.62mm M80 was adopted in 1952, sniper etc ammunition is different and the current M118LR uses IMR-4064).

On top of that Eurenco P.B. Clermont which makes Ramshot powders and supplies military ammunition loaders in many countries having bought the production rights for the type from the Olin Corporation is credited with probably the best and most sustained R&D on smallarms propellants bar none, and it has put a lot of effort into developing cool and clean burning versions, also losing ball powders' original downside of temperature sensitivity.

So, at equivalent pressures, I wouldn't expect Hunter to wear barrels out any faster than single-based extruded products with the exception of some very cool burning types such as Viht N165 and Hodgdon H1000 that are known to maximise barrel life in barrel-burning cartridges.

I've recently started researching 243 Win loads, bullets, and performance for a project on making a Howa 1500 Varminter into a clubman's occasional F-Open rifle given the cartridge's and its rifles' widespread distribution. Because the 243 is a common off the shelf number many users fail to notice that it is a fairly over bore -capacity design which as a rule work best with slow burning powders. Despite that, the loading manuals give loads for a remarkably wide range of propellants including many relatively fast burners. So powders like RS52 and N140 will work in the cartridge, but at a little low (mid 80s to 90%) fill-ratios. My gut-feeling is to go to slower burning grades even for lighter bullets. I'll get the chance later this year to prove / disprove this hypothesis as my first bullet choice is the 70gn Sierra MK and I'll try a large range of types / grades with it.

[snakeman]

Laurie

Your conclusions will be very interesting indeed

ATB

[Re-Pete]

I use RS52  in my 6BR's with very good results. MV is 2890 fps with a 30" barrel and 105gr Scenars.

Re-Pete

[blaser308]

Found N160 excellent for both 90 to 105g bullets in my 1 in 8 twist .243.

[No i deer]

My old 595 in 243 saw most of its life on 41grs of varget behind a 75gr Vmax.i will be surprised if it didn' see over 2000 rounds including the last 10 years a mate had it and he was still picking off rabbits in excess of 500yds last summer.its been hardly used since then until about 4 weeks ago that it was sold for a doner.it took 2 foxes on its last outing.load n shoot.i would worry about the barrel mesun.

[Chanonry]

Well, I am running 107 SMK over N165. Initial test loads gave incredible groupings but at 33 rounds its a little early to comment on barrel life !

[colin jalland]

I have been trying different loads in my .243 it has a 1in10 twist so i have been working with 75gr V Max at the mo but struggling a bit nothing seems to get below 1/2 moa . I tried n550 yesterday which was again 1/2moa at 42.5gr so going to try a lower charge and see what i get unless someone has a better suggestion?

Any help would be great as i get very little time .Thanks Colin

 

[No i deer]

Givem a good jump to the rifling.30 to 40 thousanths 

[colin jalland]

Yeah at 30 thou now going to try 40 next after tweaking he load a little 

[snakeman]

8 hours ago, colin jalland said:

I have been trying different loads in my .243 it has a 1in10 twist so i have been working with 75gr V Max at the mo but struggling a bit nothing seems to get below 1/2 moa . I tried n550 yesterday which was again 1/2moa at 42.5gr so going to try a lower charge and see what i get unless someone has a better suggestion?

Any help would be great as i get very little time .Thanks Colin

 

 

Colin

I too really struggled with the .243 to attain consistent groups. Although I was not being overly conscious on every individual powder and bullet I tried, or nor was I meticulous in my load development as when developing loads for other calibres, I simply didn't want to overheat the barrel or give it unnecessary wear.

If I'm honest I put it down to the T3 lite being too light, for it to achieve what I wanted out of it. I blamed powder, bullet, rifle, primer, wind, people firing next to me with muzzle-breaks, and everything else in-between, except myself .. In the end I managed to get it to shoot hole-on-hole with Hunter, but it wasn't without frustrations - I found the .243 the most finicky cartridge I've developed a load for, period.

Good luck and take time with the barrel

[No i deer]

My old 595 in 243 use to shoot real good.i saw my mate hold 2 inch groups several times from 400yds playing across the fields with the 75gr Vmax load 

[colin jalland]

No i deer yeah i used to have a good Varget load in my old .243 but as it is no longer available it's a real pain .

 

[Fox Tales]

 There is a school of thought that believes the throat erosion in the 243 is a direct result of the case design. 

 The shoulder angle and the relatively short neck , this combination directs the the blast and heat at the throat and the short neck offers little in the way of protection . 

 Logically speaking fast burning powders would only exacerbate this and I believe do . But by how much would using slower burning powders in the 243  realistically extend the barrel life ?? I ask out of genuine interest as I can't find any real figures relating to this .

 Apologies to the OP for going a little off topic . 

 

 

 

 

[Gavhowe]

I was using Norma factory ammo in my 10 twist 243 loaded with 75 vmax heads and was shooting sub 1/2 moa all day long at around 3340fps. Ammo has dried up in my local shops so decided to try loading again for it and I have had very promising results with RS62 and the 75vmax. Still working on seating depths but looking great near the top end and gaining another 100fps. 

[Chanonry]

On 4/29/2018 at 2:34 PM, Laurie said:

Despite that US Army studies have shown no reduction in military rifle barrel life between those used with single-based extruded powders and those with ball types. (All standard US military ball ammunition have been designed to use WCC produced ball powders from the St. Marks Powder Co, plant  in Florida since the 7.62mm M80 was adopted in 1952, sniper etc ammunition is different and the current M118LR uses IMR-4064).

On top of that Eurenco P.B. Clermont which makes Ramshot powders and supplies military ammunition loaders in many countries having bought the production rights for the type from the Olin Corporation is credited with probably the best and most sustained R&D on smallarms propellants bar none, and it has put a lot of effort into developing cool and clean burning versions, also losing ball powders' original downside of temperature sensitivity.

I've recently started researching 243 Win loads, bullets, and performance for a project on making a Howa 1500 Varminter into a clubman's occasional F-Open rifle given the cartridge's and its rifles' widespread distribution. Because the 243 is a common off the shelf number many users fail to notice that it is a fairly over bore -capacity design which as a rule work best with slow burning powders. Despite that, the loading manuals give loads for a remarkably wide range of propellants including many relatively fast burners. So powders like RS52 and N140 will work in the cartridge, but at a little low (mid 80s to 90%) fill-ratios. My gut-feeling is to go to slower burning grades even for lighter bullets. I'll get the chance later this year to prove / disprove this hypothesis as my first bullet choice is the 70gn Sierra MK and I'll try a large range of types / grades with it.

Are there links to this research online?

 

[Laurie]

Not that I've seen. Sierra Bullets (which has for years collaborated closely with the US Army) mentioned it in a loading manual many years back. The US Army did its research  in the aftermath of introducing the 7.62X51 round / M14 rifle and deciding on a policy of ball powders only for non-specialist 7.62 types, so I'd assume it dates from the late 50s or maybe early 60s. Almost everything that the US Government and its agencies researches is available somewhere online unless it is 'classified', .... but finding it.

With so many developments in propellants in recent years, it's dubious how much one would learn now anyway from 50 + year old research.

People shouldn't get too worked up over 'double-base'. Most recent introductions have nitroglycerin in the mix somewhere - all of the new IMR 'Endurons' for instance; every Alliant 'Reloder' grade; all ball types. Viht N100 series, RS 30/50/62, and Lovex SO extruded grades are the only true single-based types left to us now. However,  Viht N500 series aside and some of the older grades, the norm is 3-10% nitroglycerin content by weight and if loads are sensible, barrel life appears as good with these grades as with anything else. I bought a secondhand low round count Musgrave 7.62 TR rifle with a Maddco stainless barrel maybe 25 years ago, shot it regularly in TR matches all season for some five years and sold it to a fellow club member who still has it. The load was (and is) the old Sierra 155 MK and Alliant Re15. I passed the load on and the new owner still uses it. That barrel is still going well today, and the round count must be really something. As we never shot beyond 600 yards and more often than not at 300 only, the loading was mild.

Some Viht N500s have very high nitroglycerin levels - N540 was reported as 45% on its introduction many moons ago and I assume it's still very high.

What does kill barrels fast is the combination of a high-energy mix allied to advanced deterrents early burn modifying technology, in particular RS's 'EI' grades (RS 40/52/60/70/80 and some Alliant powders supplied by Nitrochemie). They will give a step increase in performance but the extension of the peak burning pressure and heat period increases the stress on the chamber throat rear end of the barrel. Don't load them up to peak pressures and performance and they should be fine. (I have an FTR rifle with a Broughton 5-groove that has had a lot of RS52 down it and its performance is holding up very well.)

With the 243 being a known barrel burner, there is a good case though for the high round-count user to choose powders carefully. Viht N160 and N165 are obvious candidates for the heavier bullets. (John Whidden keeps winning US national championships with the 'straight 243' 105 Hybrids and N160 too - ~1,300 rounds barrel accuracy life he says and remember American prone competitors string-shoot, so rounds will go downrange as fast as the target is marked and a lot faster than our TR or F-Class.) For ball powder lovers, I imagine the Ramshots will give acceptable if not in fact very good life if pressures are sensible. 

[sandtrap]

Iv just loaded some RL-15 with 65grn bullets and also with 95grn .. but the RL-15 is not best suited for the heavy bullets it should be fine for the 65grn 

Also got some super performance that I'm going to try with 65and 70grn bullets