223 70gr 1-9 cant get a group

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Moose02

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Well ive come to the conclusion my 223 Rem 700 LTR doesn't like 70gr ive tried every possible combo with 70Gr Bergers and BLC-2. I was thinking about trying Vargit but can it possibley change it that much. (Im getting 2" groups right now) With my 50 gr noslers its a tack driver but i would like to reach out 4-500 yards

so basicly im feed up for now
 
I'm assuming that your title means a 1:9" twist. If so, the problem lies with the nature of gyroscopic stability (that stability provided by rifling, ie). The longer a projectile is in relation to its diameter, the faster it has to spin to be stable. A 70 gr bullet in .223 is comparatively long and needs to be spun very rapidly. Note how 5.56mm NATO military rifles had to go to a 1:9" or even 1:7" rifling when the 62 gr SS-109 round was standardized. Your barrel is stabilizing shorter bullets perfectly according to what you say, so there's nothing essentially wrong with it; its rifling is just not up to the job you want it to do, even at 1:9".

Sorry. :redface:
 
I doubt the problem is your twist, I can shoot 77gn SMK's into 0.3 inch groups, using Varget, and RL-15. My rifle is a 1:9 twist Rem700. The 69gn bullet was designed to shoot in a 1:9 twist, these also shoot very well in my rifle, 0.5 in groups are routine with 69gn SMK bullets

PM me I will send you my load data and see how it compares
 
ATOM said:
Busted.

To be accurate, there are a lot of factors. Check out Stability at www.jbmballistics.com/calculations/calculations.shtml
Click to expand...

Busted? I don't think so. I have a 1:9 Kreiger what spits out 80 gr SMK just fine. But this does go against the grain on what should work and what really does. I did not expect it to shoot 80 grainer well but it does with 26 gr of Varget pushing it. Works to 800m but not so well at 900m.

To the OP
When the 5.56 NATO round 62 or 63 gr FMJ was first introduced to DCRA competition (yes it was free DND ammo back then) some guys shot it all the way back to 900m. Then they shot 69 gr SMK before moving to faster twist barrels and 80 gr and now some are using 90 gr/
Not all barrels like the same bullet. If you have tried eveything and it doesn't work, move on to another bullet.
 
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