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loneranger04
10-26-2012, 01:07 AM
Hey everyone. I'm new to the forum and want to first off say "thanks" for letting me join up. I've been a shooter for 40 plus years (telling my age) and currently shoot a lot of 3 gun and IDPA however have started shooting some long range matches with my recently purchased .308 and am needing some direction for reloading.

My rifle is a Savage action with a 24" bull Criterion barrel set in a Manners stock. The barrel has a 1:10 twist and I've tried several different bullets and am seeing pretty average groups (.8-1 inch range with 1" being the norm) with everything I've shot. I'm currently using SMK 175s seated .02 off the lands with 44.3gr Varget and CCI BR2s and Lapua brass. I've tried 178 gr. Hornady Amax and Nosler 168 gr competion bullets with about identical results. I'm going to be using the rifle on some long range matches with ranges starting at 300yds and going out to 1400 yds so I'd like to see some tighter groups if at all possible. My question is...has anyone here had better results with these barrels shooting heavier bullets, such as Berger 185s, or maybe lighter bullets, such as SMK 155 Palmas? The twist should shoot these 175s better than the light bullets I would think but just not seeing what I had hoped with the 175 SMKS. Hate to keep buying different bullets trying to find that "just right bullet". Hoping someone here can shed some light. Thanks.

acemisser
10-26-2012, 07:05 AM
I am shooting the 175 SMK's out of my Remington 700 with the 1 in 10 twist barrel...I have gotten some
pretty good results out to 250 in the F class matchs here..I have found that Reloader 15 is the best
powder in my rifle and I am using Federal Mag.primers and Winchester brass.The bullets jump into
the lands..My charge weight is 43.0 grains..In some manuals that is listed as over max...
I wouls continue to use it for the shoots but it only has a sporter weight barrel and gets very hot in
short order..Maybe this winter I will have it rebarrel with a bull barrel....

And like yourself I would like to shoot the 155 Lapua's but they will not shot accurate with the twist..
My thought on it is to stick with the heavy bullets for better performance in the wind..Good luck
with your shooting..John

helotaxi
10-26-2012, 09:11 AM
Twist only tells what the barrel can stabilize, not what bullets it will shoot best.

http://imageshack.us/a/img37/1791/img0015ke.jpg

That is a 5-shot group of 168gn SMKs fired from a 1:10 barrel. It was the best group of the day for sure, but the worst was still under 3/4 MOA. That barrel does not shoot 175 SMKs as well. It shoots 155gn Custom Comps better than the 175 SMKs, in fact holding just over .5 MOA @ 300yds.

If your rifle is not shooting a bullet well, it's either because the barrel "doesn't like that bullet" or you haven't found a load combination that it does like with that bullet. Barrel rate of twist isn't the issue. If you're assuming that the rifle won't shoot well with the 155gn bullets because of the twist...well you know what they say about assuming. I don't have my "definitive" reference handy, but if IIRC the Lapua 155gn Scenar is longer than the 168 SMK. Since bullet length, not weight, is what determines required rate of twist for stability, the idea that a (relatively) fast twist barrel would not shoot the longer bullet as accurately doesn't stand up to basic sanity, if rate of twist were the issue, like you assume...which it isn't.

loneranger04
10-26-2012, 10:18 AM
Yep, you're right. It's the faster twist likes the longer bullets, not heavier. Thanks.
I can't go too long because of magazine length. Wish I could buy a dozen bullets instead of a whole box.

acemisser
10-26-2012, 11:11 AM
Twist only tells what the barrel can stabilize, not what bullets it will shoot best.

http://imageshack.us/a/img37/1791/img0015ke.jpg

That is a 5-shot group of 168gn SMKs fired from a 1:10 barrel. It was the best group of the day for sure, but the worst was still under 3/4 MOA. That barrel does not shoot 175 SMKs as well. It shoots 155gn Custom Comps better than the 175 SMKs, in fact holding just over .5 MOA @ 300yds.

If your rifle is not shooting a bullet well, it's either because the barrel "doesn't like that bullet" or you haven't found a load combination that it does like with that bullet. Barrel rate of twist isn't the issue. If you're assuming that the rifle won't shoot well with the 155gn bullets because of the twist...well you know what they say about assuming. I don't have my "definitive" reference handy, but if IIRC the Lapua 155gn Scenar is longer than the 168 SMK. Since bullet length, not weight, is what determines required rate of twist for stability, the idea that a (relatively) fast twist barrel would not shoot the longer bullet as accurately doesn't stand up to basic sanity, if rate of twist were the issue, like you assume...which it isn't.

Guess I will never get it then..I tried Hornady 168 gr. match bullets in this barrel,with no luck at all..I think the best was like 1 1/4 at 100 yrd....I tried several powders and different oal.as well...It just would not shoot with any more accuracy..I guess that is why I have trouble when people like you say the twist makes no difference..I know some rifle's just seem to like every load combo available..
But like I said,it just does not work for me..Now maybe that is the issue,the length of the bullet its self..I have never tried the 155 lapua's...I just hate to buy a box and not have them work..It would be outstanding if they did though....John

Tempest
10-26-2012, 11:18 AM
Ditto on the SMK. My 10 BA is around .5 MOA at 400 yards on a good day using either Black Hills 168 or 175g SMK.

Hornady for some reason have not been as good as BHA in my rifle.

loneranger04
10-26-2012, 12:23 PM
Twist is one of those things that cause a rifle to shoot well with one bullet and not so well with another. I'm with you, acemisser, I hate to buy another box of bullets only to see that I'm no better off than my 175 SMKs that cost $10-!5 more than SMKs. But helotaxi is right in that the faster twist like longer bullets...usually. I shot black powder for years and usually you used a 1:66 barrel for round ball and a 1:24 or so for conical and sabots. I guess the real answer to my question, which is which bullet will shoot better, can only be answered by buying more bullets and working up more loads. Oh well, it's fun to play anyway. Just getting a little expensive.

Thanks to all the replies.

Jamie
10-26-2012, 01:04 PM
Twist only stabilizes a bullet, it doesn't dictate accuracy. Now the argument can be stated that if a bullet is not not stable then it cannot be accurate. That is true but we are past that here. Just because a rifle has a fast twist does NOT mean it will shoot heavy bullets accurately. It just means they will make round holes in the targets when they hit instead of key-holing.

I have a RRA in .223 with 1:8 twist. It will stabilize 75 grain Amaxes all day but will shoot them into a 1.5" group. On the other hand it will put 5, 52 grain NBTs into less than .5"

The barrel will tell you what it likes, not the twist rate and some barrels are picky and takes some work to find the sweet spot.

wbm
10-26-2012, 01:29 PM
Having shot the 175 Sierra in both M1A and bolt guns I would opt for a powder other than Varget. I know lot's of shooters have had great success with Varget but I never got it to shoot better than some other powders in the .308. Personally I would work with IMR4064 with the 175 match king. The latest military ammunition for long range, M118LR, uses 41.7g of IMR4064 with the 175g SMK. I would start there.

acemisser
10-26-2012, 01:41 PM
all well and good for some barrels...I do not agree with some of the stuff written..I have to prove it to myself..

I had one fellow tell me he was shooting 110 gr. bullets in a 1 in 10 twist with great accuracy....come to find out
he was talking about hitting a pie plate at 100 yards..lol Anyway,I guess I am gonna have to order a box of the
155 lapua and find out for myself..I appreciate all the comments and replies...John

For what its worth Lupua reccomends a 1 in 12 for their 1555 grain match bullets....So i'm staying with the 175 SMK or a bit heavier.....Honest Ingiun...

teele1
10-26-2012, 02:17 PM
My CBI 30" 1-11 loves Berger 185 BTTLR (30418) bullets with either Varget or RL-17. Defiantly shoots tighter with these than my Sierra 175 Match Kings

Hooker
10-26-2012, 04:10 PM
Try 43 grains of RL 15 with 175s. 155 Sierra Palmas shot well out of my barrel also.

jim_k
10-26-2012, 05:02 PM
Do not seat bullets .02 from the lands. That's too close, and tolerances being imperfect, you will likely get some rounds touching and some rounds off the lands. Set back 0.010" and try again. Also, no matter what kind of stock you have, it may need to be bedded. I have the McMillan 10FP, and it shot right at 0.9" for 5 shot groups until it was bedded; then it shot 0.38" with the same ammo. Depending on what makes contact, if there are aluminum bedding blocks in your stock, you can use J-B Weld to put some on each block, of course with release agent. Too much diddling with various bullets will make you crazy! The SMK will do fine; Noslers ditto; Bergers jump just fine (I've shot under 0.3" with Bergers jumping 0.25"). Also, break-ins vary, and if you do these things, and don't get under 0.5", get the Tubb Fire-lapping system, called Final Finish.
Jim

rjtfroggy
10-26-2012, 05:24 PM
!55 smk's pushed by 42.6 gr. IMR 4895 out of a 1:10 cbi 26" after playing a little with the seating and settling at 0.018 off the lands gave me .335 5 shot groups at 100 and opened up to.645at 200.
You will only find out after you try.

stangfish
10-26-2012, 08:38 PM
Do not seat bullets .02 from the lands. That's too close, and tolerances being imperfect, you will likely get some rounds touching and some rounds off the lands. Set back 0.010" and try again. Also, no matter what kind of stock you have, it may need to be bedded. I have the McMillan 10FP, and it shot right at 0.9" for 5 shot groups until it was bedded; then it shot 0.38" with the same ammo. Depending on what makes contact, if there are aluminum bedding blocks in your stock, you can use J-B Weld to put some on each block, of course with release agent. Too much diddling with various bullets will make you crazy! The SMK will do fine; Noslers ditto; Bergers jump just fine (I've shot under 0.3" with Bergers jumping 0.25"). Also, break-ins vary, and if you do these things, and don't get under 0.5", get the Tubb Fire-lapping system, called Final Finish.
Jim

Im not sure what to think about this. Dont seat them .020 off the lands because some will touch and some will be off. Last time I checked if they are .020 off the lands then they are not touching the lands they are .020 off the lands. Im thinking that they are not .040 off the lands because they are .020 off the lands.You may be much more knowledgeable than I but that statement does not have reason to me unless you are not aware that COAL and the ogive are different distances or possibly we are not experienced enough to know this. Im not looking for an arguement but many people put bergers in the lands on a stadard chamber with great results.
I am but a 580 F/TR shooter doing it with 155's CC's in a CBI 10T 28". Almost everyone that beats me has a berger.... in the lands.

Blue Avenger
10-26-2012, 08:57 PM
Do not seat bullets .02 from the lands. That's too close, and tolerances being imperfect, you will likely get some rounds touching and some rounds off the lands. Set back 0.010" and try again.
Jim

while were at it, my poor learning shows .010 is closer then .020 or are you now wanting .030? another confused person.

jim_k
10-26-2012, 09:49 PM
Im not sure what to think about this. Dont seat them .020 off the lands because some will touch and some will be off. Last time I checked if they are .020 off the lands then they are not touching the lands they are .020 off the lands. Im thinking that they are not .040 off the lands because they are .020 off the lands.You may be much more knowledgeable than I but that statement does not have reason to me unless you are not aware that COAL and the ogive are different distances or possibly we are not experienced enough to know this. Im not looking for an arguement but many people put bergers in the lands on a stadard chamber with great results.
I am but a 580 F/TR shooter doing it with 155's CC's in a CBI 10T 28". Almost everyone that beats me has a berger.... in the lands.

You are right about the seating depth. I misinterpreted 0.02" as 0.002", and you should not seat "barely off" the lands, for the reason I stated. Either shorter OAL or into the lands. I agree that [U]usually[U] the rifle will shoot better jammed into the lands, and I don't think there's anywhere near the "high-pressure" risk that people typically caution about. I have quit seating into the lands, since my aiming error is always more than any advantage I could see on the target.
Thanks for correcting my error. Those Berger-shootin' F/TR folks also obsess about bullet pointers and meplat uniformity, and I don't blame you if you don't do those things.
Jim

stangfish
10-26-2012, 10:16 PM
Those Berger-shootin' F/TR folks also obsess about bullet pointers and meplat uniformity, and I don't blame you if you don't do those things.
Jim

He he...obsession is relative!

loneranger04
10-26-2012, 11:04 PM
I'm actually seating bullets using the ogive as a measurement, instead of the COL. Bullet tips are not very uniform so COLs aren't all that meaningful, except considering length of magazine. I'm shooting long distances and would prefer the 175s over the 155s however I think my next bullet will be the Berger 185s BTTLRs because of the BCs and long range shooting. Unfortunately my home range will only support shooting 200 yds and I won't know how any of them perform out to over 1000 yards until I shoot a match.

Thanks for all the info.

CharlieNC
10-27-2012, 10:51 AM
[QUOTE
But like I said,it just does not work for me..Now maybe that is the issue,the length of the bullet its self..I have never tried the 155 lapua's...I just hate to buy a box and not have them work..It would be outstanding if they did though....John[/QUOTE]

You can buy a few bullets to try from bulletsamples.com; also seems like I read Brownells sells sample quantities. With 10 or so you should be able to tell if a new bullet has good potential or not.