150 gr bullets in a 1:10 twist barrel- will it suck?

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GunNewb

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Looking to get an 18.5" 1:10 twist criterion barrel for my norinco m14 as well as a bunch of other stuff to accurize it.


Im kinda worried though that the reasonably priced practice bullets (150gr FMJBT hornadys) wont fire well because of the 1:10 twist. Does the length of the barrel matter as far as twist rate at all- since the barrel is so short will it twist the bullet like a 1:11 22" barrrel?


Anyone have any idea on what the effects thatll have on accuracy?
 
1:10 twist will spin the bullet faster than a 1:11 twist so it's actually a good thing as it doesn't affect the lighter bullet accuracy but will most certainly help if you ever decide to shoot the heavier ones...although, that may be a moot point as my 1:12 twist Remington 700 Varmint as no issues stabalizing various 175-190gr match and hunting boat-tail bullets. Barrel lenght is another moot point...the difference in bullet spin between in a 22'' 1:10 twist barrel VS an 18.5" 1:10 twist barrel isn't even something that would make a significant difference on paper let alone in the field.

Unlike some other calibers and chamberings...with the 308 Winchester and 7.62 x 51mm Nato chamberings it is impossible spin any bullet fast enough for it to disintegrate in mid air.
 
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GunNewb said:
Looking to get an 18.5" 1:10 twist criterion barrel for my norinco m14 as well as a bunch of other stuff to accurize it.


Im kinda worried though that the reasonably priced practice bullets (150gr FMJBT hornadys) wont fire well because of the 1:10 twist. Does the length of the barrel matter as far as twist rate at all- since the barrel is so short will it twist the bullet like a 1:11 22" barrrel?


Anyone have any idea on what the effects thatll have on accuracy?
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The 1:10" twist will work just fine with the 150FMJBTs (and for that matter, all other bullets you might want to fire from your M14).

Barrel length does not directly matter. (there's a *very* small effect due to bullet speed, but in most circumstances, including this one, it can be ignored).

Your accuracy will depend on all sorts of things, such as the quality of the barrel, how well your rifle is bedded, how well all the loose and jangly M14 parts are set up, etc. These factors *by far* outweigh concerns of whether a 1-14" twist barrel is slightly more accurate than a 1-10" twist.
 
Just my 2 cents here but when you are building a rifle for a purpose it's hard to plan it around one specific bullet , you could do all the right things with the build and then find out that it just won't shoot that bullet I am also building the same type of rifle m305 scoped and for learning how to shoot targets in a more practical manner rather than from a bench shooting a known distance

I don't have much faith in the 150gr hpbt bc is kinda low and the results I had with them in my bolt gun were not to great ... But you never know until you try if my rifle will shoot them I will use them. but right now I'm thinking of useing 168 smk or 155smk they are well proven as an accurate bullet and available in boxes of 500 if you are going to buy a new barrel I would get one that has the proven recipe for preformance ... The m14 has been used in rifle matches for manny years there ought to be a proven barrel twist and legth that will preform
 
rnbra-shooter said:
Your accuracy will depend on all sorts of things, such as the quality of the barrel, how well your rifle is bedded, how well all the loose and jangly M14 parts are set up, etc. These factors *by far* outweigh concerns of whether a 1-14" twist barrel is slightly more accurate than a 1-10" twist.
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+1 1-10" is a good all around twist for most .308cal bullets from 130gr-220gr bullets in my limited experience....
 
150s shoot best with a 1:13 or 1:14 but that assumes 2800+ FPS velocities. You will probably find that 1:10 barrel will shoot tighter groups with fewer flyers if you slow them down a bit and run them at 2500-2600 fps – assuming you roll your own. Try for a load that just barely cycles the action.

If you are shooting a Norinco M14 don’t worry about the bullet BC. The rifle is not likely accurate enough to get value out of high BC bullets anyway.
 
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BadAsMo said:
150s shoot best with a 1:13 or 1:14 ...
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That's advice from the world of target rifles made with match barrel. And even there it's borderline debatable... one of the top US Palma shooters used a 1-10" twist rifle to shoot 155s, a combination that is clearly "wrong" (it certainly goes against all conventional wisdom) and nobody would intentionally build. And he shot that rifle very, very well.

In answer to the OP's question 150 gr bullets in a 1:10 twist barrel- will it suck? the answer is easily, "NO - go ahead and get that barrel".
 
The point is that a 10 inch twist is a bit fast for a 150 grain bullet so he will probably find that his accuracy would be slightly better if he does not run them at max pressure. It's a simple rule... If the twist is too fast then slow them down, when the twist is too slow you gotta drive them harder.

Sure you can run premium bullets through a premium barrel and shoot good groups. I'm not suggesting that is not possible. The problem is in this case we are talking about an M14 with less than perfect ammo so dont expect to be shooting flies.

If the load is kept mild the groups will probably be slightly better than a hot load.
 
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