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308 175 gr bullet makes which works best


Richiew

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Hi All 

 

Found good results with Lapua scenar and scenar L , berger 155.5 fullbore ,amax 155 ,and sierra 155 tmk's. Question is I would like to try either 175 /185 weight bullets from the same makers and would like to hear peoples views regarding - secant /tangent/hybrid successes . Rifle is Accuracy International AT 308  which seems to have long throat but shoots well with coal lengths of 2.8 to 2.9 .Thanks in advance for your replies .

                 Cheers Richie

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I load 175 SMKs over Vhit N150 in my Rem 700P.

For me, max load is 45.5gr loaded to standard COL. 

44gr and 45.5 were my acurate loads, but 45.5gr started to give hard bolt lift so I stick to the 44gr load.

My max distance so far with these has only been 600m, so can't give any more info for further. I' think the Berger 185 jugs are of the go to bullets for longer range.

Just for info, my 26 inch barrel gave the following load velocities with the 175 SMK and N150, standard Lapua brass, Federal 210 primer.

43gr.......2615fps

44gr.......2675,

44.5......2700,

45........2735,

45.5......2745....Stiff bolt.

 

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The 175g SMK is proven bullet out to 7/800yds.... B/O measurement is: 2.120 ...This gives me a COAL of 2.865 which is 60thou off the lands.

I started load development at 38.5g and worked up to 42.0g (of N150)

Had no reason to load higher charge due to it being fired out to only 500yds max - reverted to 40.6g of N150 and is spot on at 2472fps

This was out of 1/11" twist and 24" Tikka

Your own reloading rules apply :excl:

ATB

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The outstanding bullets in this bracket are Berger's two 185s, the Long-Range BT Juggernaut and the newer Hybrid. The latter may be too long though for your throat / and magazine operation. Both models are very expensive now and usually difficult to find in stock. Their RRPs are £68.75 and £71.98 / 100 respectively.

The 175gn Berger LR BT is a very sound design, but the new Sierra TMK has a virtually identical BC and is somewhat cheaper. I've been very impressed by TMK quality and results in the 7mm 160, so if this bullet is as well designed and made (and I would expect it to be so) it should be a good performer. The TMK has a 10% higher BC than the older SMK - I believe it is a wider redesign than just sticking an acetyl tip on the old model.

Berger's older 168, 175 and 185gn VLDs are ballistically very competent, but are full-house VLD form designs with very aggressive secant ogive front ends. This can make them hard work to 'tune'. The 168gn Hybrid is a superb long range performer and can be driven very fast, but it needs to be treated like a VLD and seated into the lands in most barrels / chambers.

http://bulletin.accurateshooter.com/2015/05/litz-field-tests-bcs-of-sierra-tipped-matchkings/

Hornady makes a 178gn HPBT Match, one of its new lines that were suspended during the great US components shortage period but is now back in production. Unlike the Sierras and Bergers it has a mild secant ogive. I've found it 'OK', but it hasn't been an outstanding performer in my 308 FTR rifle. Hornady also now produces 178gn thirties in the two ELD tipped varieties and as with most designs from this company, they're secant ogive. I've seen nothing at all so far in feedback on this particular bullet. It does appear to have got the old AMax's boattail angle 'sorted'. On its claimed BC, it's in the same bracket as the TMK and Berger LRBT. The old AMax thirties are poor very long-range bullets with the sole exception of the 208gn model.

Lapua makes both 175gn and 185gn Scenars, the former a recent 'L' type introduction. Neither has a high BC for its weight, in fact the 185 in particular has a very poor one. Both are well made and shoot well and are easy to tune being traditional tangent ogive nose forms.  They are a lot cheaper than the American bullets. Another very old Lapua design is still listed, the antediluvian 185gn D46 rebated boat-tail FMJBT, a successor to designs originally cooked up in the 1920s and 30s to make Finnish 7.62X53R Maxim guns shoot out to 5,000 metres ranges. This is a reasonably efficient design that works very well in some rifles and is very easy to tune. At around £45 / 100 it's a cheap bullet by today's standards.

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Thanks very much for your replies , lots of great info to play with ,will get some of the above to try depending on availabilty/supply., off to catterick soon to try the new loads of 155's seated to 2.85 .old amax and the bergers work very well the lapua standard and L type are good and the 155 TMK need to find best seating depth . had a few issues with not getting enough bullet in the neck at 2.9 coal and had smoky cases as if the case hadnt expanded to chamber size before the bullet was on its way . best group has been bergers at 10 shots through a 1/2" hole  ,so would like to see the same for heavier bullets. 

ps Why do lots of people rubbish the 168 gr    bullets  , hornady 168 bthp match factory ammo didnt suit the rifle btw  , also PPU ammogroup sizes were 2" at 100m 

 

 cheers Richie .

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2 minutes ago, Richiew said:

ps Why do lots of people rubbish the 168 gr    bullets  , hornady 168 bthp match factory ammo didnt suit the rifle btw  , also PPU ammogroup sizes were 2" at 100m  .

Other than the 168gn Berger BT and Hybrid models and now the newish Sierra TMK, all  American 168s are short-range designs with tail angles that are too steep for long-range use. (This also applies to the now discontinued Hornady AMax.) The AMax aside, they are also very blunt, high drag bullets by today's standards.

They basically all ape the original .30 168gn the Sierra MatchKing (or 'International' as it was originally named) which was introduced in the 1960s when .30-06 and 308 were used for almost every discipline and it was specifically designed for 300 metre shooting. It performed brilliantly in this role (still does) and was also found to be an excellent 600 yard bullet in the US .30-06 M1 Garand rifle, later the M1A / M14 7.62 / .308 rifles when they were the norm for US High-Power Service Rifle competition. But go much beyond 600, certainly beyond 800 yards ........

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Thanks again  Laurie ,Aha boat tail angle rears its ugly head again!!!!!!

looks like I'll stick to trying the 175's and 185's and N 150 seems to be the prefered powder? . Im wanting to find the most accurate loads to suit 155 and 175/185 then settle to making a batch of these to keep powder types to a minimum . All good at the moment with n135  for the 155s.  Once ive found the best load ill stick with it as long as supplies are avasilable .

 

 Cheers   Richie

 

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I only use 175 TMKs now for long range work in .308.  Nothing else I've tried close to the price matches their performance in my rifle, nor their consistency which on my last batch was within 1 or 2 thou base to ogive measurements.  They are incredibly consistent in manufacture and will tolerate long jumps due to their tangent-esque ogive profile.  Loaded to mag length, they seem to perform very well indeed. Although I have found several nodes with every TMK in every calibre that I use, most cases it's the faster they're pushed where I seem to get the best results.

In .308, I use 44.2gr RS50 and that comfortably makes them a very useful and accurate 1000 yard round at the velocities I'm getting with this combination although not up to the more slippery 6.5 and 7mm bullets in performance.

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I think a fair amount of folks use N150 with 155s, I have very good results with N140.

My accurate load with the 155SMK is 43.5gr N140.

44.5gr is max with my combination. 26" barrel Remington 700.

I intend to work up a load with 155 Scenars with N150 to see if I can increase the FPS with my setup.

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Hi All    

many thanks for replies ,lots of great info especially re the TMKs which seem to be easier to get hold of compared to Bergers  ,.. Deadcenter have look at my post from september for info on 155 s with n135 . 

Looked at the berger handbook and it quotes N135 to be a powder for the 175s so in theory one powder could do both duties 155 and 175 loadings. Ive got quite a bit to use up yet before trying something new , seems N 140 is frowned upon from a few old hands in our club for 155 reloading ???? not sure why its usually from the tikka shooters so poss twist related . 

Any ideas what the new amalgamation of Lapua and Berger will bring ?  .

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Rich, like V 135 in the 30 BR(1.5 Barnes-a short 308 case,so considerably reduced capacity)-bullets are 125g; 135 seems a bit fast for 155g ,and def 175g. Many shooters use V140 for 155g and maybe 150 for 175g. A powder may work-as in propela the bullet fairly well,but is unlikely to  be the best option for such a wide range of bullet weights...which is why there is a range of powders......(cf V 130/133 for the lighter 224 and 6mm bullets) and v160 for heavier larger calibre bullets....

   It's unlikely the 'old hands'  are all very  well up on ,say,the detail Laurie provides ( eg that most 168s are not up to 800y+ with good  performance),and it's not likely a twist rate issue,as Tikkas have more or less standard twists in 308,like  most factory rifles...custom barrels  may have  other twists and do better... 

I daresay,very occasionally, a few old hands  might be  somewhat limited in their up to date experience of new developments in bullet design,powders and current best performers. Ask them what they think of the old fangled 284Win,a current favourite at 1000y.

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Thanks for reply gbal

been back at the berger manual again and N140 looks suitable for both the 155s and 175s or if looking at viht web page 175s loads are n140 n150 n550 n540   funny though n135 is a reccommended powder for scenar L 175s. the N140 seems to hit the most accurate loads in the 150 upto 185 gr range too .berger only quotes n550 for their 185s from that powder maker . checked with hornady and nosler manuals and all give confusing info but n140 does come out a winner of Vihts range . 

cheers    

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N140 is usable with 175 grain projectiles BUT is not ideal.  It is a little peaky and has a tendency to suffer spikes in pressure when used higher up the pressure ladder, especially where heavier bullets are concerned.  My shoulder can attest to that!  N150 is a more sensible choice.  RS62 is also a good choice for 175 and heavier, although you can also use RS50 without the same pressure signs as when using N140 with 175 bullets.  Just because Vhit list those powders with those bullet combinations doesn't make them ideal.

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Interesting posts...

I've been playing with TMK175's with RS50 @ 44.3gr in Lapua LR Cases and 44.7gr in Lapua SR Cases (Murom Primers for both, 2.250" Ogive - 13 thou jump) for quite some time and was getting good groups at 1000 (2765fps, 1 in 10 twist, 28").

Unfortunately, the last batch of TMK's I bought where definitely of a lower build quality than the previous ones (I buy them in 1000's) the latest batch has the poly tip offset from the jacket which opens my groups up considerably.

I switched to Juggernauts using the same cases/ powder/ primer combination and all's well again/ accuracy has returned.

I now have Berger 155.5gr to try with RS50 (I've tried N150 several times in several rifles but, for me, I cant get it to work).

FWIW - I bought a Bullet Pointing System from the Shooting Shed as an insert to my Redding Die to point SMK175's and these perform like for like with TMK175's - and they're cheaper!

The newest/ latest purchased SMK's appear to be "pointed" as standard which will save buying a pointing system.  

Cheers

 

 

 

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Cheers Stu47       when and where were the TMKs From as it might put me off buying too many .

berger quality does seem to be very consistent ,175lrbt and 185 jugs are my next to try  , although for the 155.5 FB  the sizes quoted in their reloading manual doesnt match actual measured with digital calipers. Re 155s   have some lapua scenar-L and comparing these to standard scenars the L`s look to be pointed ie have a second angle at the tip and also the hole at the end is much smaller than the std scenars .

cheers   Richie 

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They where back ordered as i wanted  them all from the same batch from a reputable source (don't want to name them as its an OEM issue not a supplier issue).

I received them 2 months ago and measured them (as i do for all bullets, weight/ base to ogive, OAL, bearing surface) and all seemed good dimension wise but the tips are noticeably offset - enough for your thumb to feel a distinct "step" in the transition from brass to poly tip. In all previous TMK' batches this transition was seemless. 

I loaded them up anyway as its all i had. Don't get me wrong they still achieved 1 MOA at 1000 but this was disappointing as previous lots had achieved 0.7 MOA average at 1000.   

I'm going to load develop the 155.5's but as it stands right now my "go to" load is the pointy SMK 175's.

I have a very good load for the 175 OTM's and these are by far the most accurate load i have but finding them is my biggest problem!

 

 

 

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checked my 155 tmks and can see a step where the tip joins the copper , Amax `s are a much better seamless join .sent out some emails to check on availability of Bergers so will see what turns up .

 

thanks for the info ,it does pay to get as much info as poss . as they say knowledge is power !!

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My personal experience with the Berger 155,5 / 175 and 185 is with the vhita gunpowder. 47/46/45 grais as the initial tuning process in the upper part. 920/890/870 ms is what I got with my 32 "barrel

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Just now, Cienfuegos said:

Mi experiencia personal con el Berger 155,5 / 175 y 185 es con la pólvora vhita. 47/46/45 grais como el proceso de sintonización inicial en la parte superior. 920/890/870 ms es lo que obtuve con mi barril de 32 "

They are at the limit of pressures, which begins to deform the brass. The load is usually 0.2 up or down.

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15 hours ago, stu47 said:

Interesting posts...

I've been playing with TMK175's with RS50 @ 44.3gr in Lapua LR Cases and 44.7gr in Lapua SR Cases (Murom Primers for both, 2.250" Ogive - 13 thou jump) for quite some time and was getting good groups at 1000 (2765fps, 1 in 10 twist, 28").

Unfortunately, the last batch of TMK's I bought where definitely of a lower build quality than the previous ones (I buy them in 1000's) the latest batch has the poly tip offset from the jacket which opens my groups up considerably.

I switched to Juggernauts using the same cases/ powder/ primer combination and all's well again/ accuracy has returned.

I now have Berger 155.5gr to try with RS50 (I've tried N150 several times in several rifles but, for me, I cant get it to work).

FWIW - I bought a Bullet Pointing System from the Shooting Shed as an insert to my Redding Die to point SMK175's and these perform like for like with TMK175's - and they're cheaper!

The newest/ latest purchased SMK's appear to be "pointed" as standard which will save buying a pointing system.  

Cheers

 

 

 

That's a similar load to mine which is 44.2gr RS50/TMK175 @ 2.8COAL for 2662fps in a 24 inch 1/11 barrel.  Will be trying it at LR this week but it gave almost one hole 100yd groups.  I haven't checked the tips as you describe and don't know what effect this will have until tested at longer range.  I guess that there may be a possibility of inconsistent BC drop-off rates between bullets but we'll see how they group.  You haven't mentioned if your 1000 yd groups dropped off in precision with this latest batch?  If not, is there anything to worry about?

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Hi VarmLR,

In my second post above replying to Richiew I describe the accuracy drop off I observed - 1 moa instead of the 0.7 moa I was expecting.

With the tips offset it will definitely affect the bullet, especially as MV decreases with range as the bullet is unbalanced (at an initial MV of 2765fps mine are roughly spinning at 199000 rpm) so any inbalance will show up in loss of accuracy.

Hopefully, Sierra will address the issue and the TMK will again become my bullet of choice. 

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15 hours ago, stu47 said:

Hi VarmLR,

In my second post above replying to Richiew I describe the accuracy drop off I observed - 1 moa instead of the 0.7 moa I was expecting.

With the tips offset it will definitely affect the bullet, especially as MV decreases with range as the bullet is unbalanced (at an initial MV of 2765fps mine are roughly spinning at 199000 rpm) so any inbalance will show up in loss of accuracy.

Hopefully, Sierra will address the issue and the TMK will again become my bullet of choice. 

Sorry,  yes, don't know how I missed that!

My only observations are that when you mention a drop-off in  accuracy from 0.7moa to 1moa, at 1000 yards wouldn't the slightest environmental condition changes contribute as much, if not more, to this difference?  After all, shooting a 7.3 inch group one day then shooting a 10.5 inch group the next wouldn't ring alarm bells with me as being anything significant unless the conditions were exactly the same and my own performance was exactly the same.  If, playing devil's advocate for one moment, we assume that your starting velocities are the same at 2765 fps, then the difference in drop for the wider group is ((10.5-7.3)/2) = 1.6 inches at 1000 yards assuming everything else is exactly the same (which it won't be) and assuming the use of averages and not extremes (fair enough in the circumstances).

Given a G7 BC for the 175 of 0.267 and using standard press/temp, the drop at 1000 yards given a 2765m/s MV is 345.2 inches.  To account for the extra 1.6 inch difference, fudging just the MV leads to an difference (average) of just 5 fps which in the grand scheme of things could be down to reloading batch variation or just the conditions on the day being different.  I get your point though.  Any inconsistency has to be viewed with suspicion and isn't what one looks for in a long range bullet.  I'll report back on how I got on with mine later in the week.  Best I've managed in my rifle previously at this range was 1.2 moa using 190 SMKs from a 24 inch 1/11 twist so I'll be interested to see how these compare.

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The new electronic targets that are available for use at Bisley are able to calculate the group size immediately on completion of firing a string. I tend to fire 10 rounds then gain this information so I can track how I'm doing throughout the day. The calculated group size is just that, the size of the group - no need to half it, hence why it is used as the standard at which (most) competitions are scored.

When firing older batches of TMK's I had several groups of 0.7 MOA (or better) but on my last visit all groups fired returned only 1 MOA, when i switched to Juggernaugts (same day, conditions etc...) I was able to get 0.7 MOA again. This, coupled with the visual difference in the latest batch of TMK's, has led me to believe that the offset tips are a likely cause. 

The TMK 175 is a fine bullet for use at 1000 yds, its not the best out there but then neither is it the most expensive and 0.7 MOA is a good return given my level of skill/ equipment. That said, I want the best return for my efforts when you consider i won't get much change out of £300 for a days shooting at Bisley (day off work, fuel, consumables etc...) so if I have to spend another £15/20 on a box of bullets to get the results I'm after its not the end of the world.

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