F T/R Competition What grain VLD should I use

captcoop

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Minuteman
Jan 22, 2012
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Daphne, Alabama
I'm shooting a 308 with a 1:10 Shilen barrel, with a match chamber . What grain vld should I shoot? Currently I'm shooting 168 SMK's until they are gone. The BC is really low for this one. Should I try the 168 match VLd with a BC of .4730 or the 175 @ .4980 or jump all the way up to the 185 @ .5490? Or will the extra bullet weight over a 60 shot string with sighters punish the shoulder even more? What do y'all suggest? The BC of The 168 SMK's is .4620 of which I'm doing away with.
 
Catpoop, for 600 yards, the BC is not THAT critical because your bullets will easily get to the target solidly supersonic. The higher BC will reduce the wind deflection so that is an advantage. On the other hand your apprehension about increased recoil with the heavier bullets is well founded, especially since the rifle you are describing is probably fairly light; you did say it was a 24 inch barrel. It may become a question of increased BC vs increased accuracy (less flinching and fatigue.) The gains in BC for the 175 is mouse nuts for 600 yards.

You might want to look at the 155 gr offerings as an alternative or see if you can get a good 168 flying, something better than the SMK.
 
If you'er in F/class then it's about competing. What are the other shooters using? what's winning? Do you want to compete or just get practice? Most competitors use the highest b.c. their gun can stableize and group, and not just on a "bluebird day" but overall when the wind is making everybody cuss. Competition is getting tougher by the month. A friend of mine that I got started in f/class just 2 1/2 years ago "cleaned" his target this year at 600yds. Unheard of 3-4 years ago. I don't know what it's like in Alabama but in N.C. comps are getting fierce. Most are using the higher weight hybrids, etc. It's all about what you expect out of the sport. With your 1/10 twist you would be ok with neighborhood of 200 gr. easy. Mine is 11.25 and it likes the Berger 185's
 
I am in the same boat as you. I just rebarreled to a Rock 10 twist in 308win on my R700. I will be running 175gr smk's until they are gone. They do well, but I want better. The guys shooting F-class T/R in my neighborhood, like the 185gr bergers and the 200gr bergers for their 308's.

I am leaning towards the 185gr bergers when I get to that point to get the BC gain w/ out much of a drop in MV. I've watched guys clean house with the berger 185's never with the SMK's. You went with a 10 twist for a reason, shoot the heavies and enjoy the BC. It will help if you plan on going out to 1k.
 
Try a few different ones and let the gun tell you. Mine likes the 185 Bergers the best. Doesn't hate the 155 Lapuas either. Pick ones that have the BC and velocity possibility you are looking for and just give it a go. I know I need all the help I can get from a high BC - even at 600 yards.
 
I'm shooting a 308 with a 1:10 Shilen barrel, with a match chamber . What grain vld should I shoot? Currently I'm shooting 168 SMK's until they are gone. The BC is really low for this one. Should I try the 168 match VLd with a BC of .4730 or the 175 @ .4980 or jump all the way up to the 185 @ .5490? Or will the extra bullet weight over a 60 shot string with sighters punish the shoulder even more? What do y'all suggest? The BC of The 168 SMK's is .4620 of which I'm doing away with.

Which match chamber are you running? Whole bunch of 308 "match" chambers out there with various amounts of freebore, to give you a good answer I'd need to know how much freebore is present in chamber.
24" bbl I'd be looking at heavier bullets over the lighter bullets.
 
I'm not sure on the reamer. My gunsmith said it would be really tight with FGMM. . I'm using handloads now about .010 off the lands with SMK's. I want to shoot a high BC bullet . I don't plan on competing at 1000 yards until I get a higher magnification. The gun range I use has 600 and 1000 yard targets for F class. I plan on shooting 1k, but for fun. They have steel also .
 
When the gun was built I tried FGMM 168 and 175, Southwest Ammo 155 Scenars, 178 Amax's. the 155's didn't do well at all, a little tuning for that liad and they would probably do better. The FGMM 168 and the SWA 178 amax was by far the best ( factory ammo) with the 178 edging out the FgMM. My handload now is 41 grains of IMR 4895 . It shoots consistent 1/2" groups .
 
Based on your comment that "FGMM would be tight" I'll take that to mean it has fairly short freebore length.

Berger 185 hybrid, 175 / 185 Match BT LR or even the 168 hybrid should be the better fitting bullets to your chamber. I'd jump the Berger bullets 0.040" to start, increase jump if needed to fine tune load.
Any of the above mentioned bullets will get you to 1K easy enough if desired.