.308 FTR bullet weight and twist choice.

Dogleg

Dogleg

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If you were starting out with a clean piece of paper for a .308 FTR rifle, what bullets(weights) and twist would you start at? If there's a simple, "everybody knows that" choice, so much the better. ;)
 
what distances are you wishing to shoot at?

are you shooting competitively or not?

depending on your answers the solution will vary

Jeff
 
For nowadays if I start from scratch I would focus on the 195-200gn bullets for FTR and leaning more toward the high BC 200 bullets. IMO they offer the best balance between recoil, ballistics and ease of tuning from my experience this far. I would now start with a barrel with my ideal balance 9.5t rate (maybe a 9t) it will be able to stabilize all if not most of all the long high BC 200s bullets without adding to much addition barrel torque when shooting. Definitely no less than a 10t rate. In either a standard 6 or 4 groove configuration.
 
The no brainer set up is a 185gr Juggernaut with an 11 twist barrel, 15 to 20 thou OFF the lands, Varget in quality brass to reach 2700'ish FPS from a 30" barrel.

My choice for the last 1 1/2 yrs has been the Sierra 195gr TMK, 10 thou off the lands, Varget in the 2600'ish fps from a 30" barrel. Has worked very well close and far in calm and very very high winds. One of my faves for ease of driving and consistency on target. 10 twist for these bullets.... can also be set up to mag feed

I am currently testing some of the new gen 200gr bullets including the 200gr MK and the Berger 200-20X so will know more after a few matches and rds downrange. The numbers looks good but I expect these to need more tweaking then the Sierra 195's or Jugg.

Jerry
 
TrxR said:
Jerry what bullets will a 1 in 10.33 twist handle ? Im going to be running 185 juggernaughts for now.
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Load and shoot.. you will know real fast if the barrel and the Juggs work together. The node is around 2700'ish fps... at 300yds/m, it will either cluster in a hole or it will not.

That is the best way to confirm any of the bullet options... they are typically well manf so the question is whether they stabilise well in any given barrel. If you can't get them to cluster within their desired velocity and/or powder charge range (Varget or H4895), drop that bullet and move on.

Jerry
 
Jefferson said:
what distances are you wishing to shoot at?

are you shooting competitively or not?

depending on your answers the solution will vary

Jeff
Click to expand...

That's a fair question. I shoot out to 1000 regularly and do the odd competition. Up until now I've been happy enough shooting my long range hunting and steel bashing rifles in FO once in a while using a bipod and shooting in FTR out to 600 with a 1-8 .223 that bears more than a passing resemblance to a gopher gun. I'm just thinking about wading out a little deeper with a real FTR gun and see where that goes. Optimizing the .308 seems like the logical place to start.
 
Mystic Precision said:
Load and shoot.. you will know real fast if the barrel and the Juggs work together. The node is around 2700'ish fps... at 300yds/m, it will either cluster in a hole or it will not.

That is the best way to confirm any of the bullet options... they are typically well manf so the question is whether they stabilise well in any given barrel. If you can't get them to cluster within their desired velocity and/or powder charge range (Varget or H4895), drop that bullet and move on.

Jerry
Click to expand...

Thanks Jerry it does currently shoot the 185's but I was wondering if the 1 in 10.33 would stabilize any heavier bullets if i wanted to try?
 
308BAR said:
For nowadays if I start from scratch I would focus on the 195-200gn bullets for FTR and leaning more toward the high BC 200 bullets. IMO they offer the best balance between recoil, ballistics and ease of tuning from my experience this far. I would now start with a barrel with my ideal balance 9.5t rate (maybe a 9t) it will be able to stabilize all if not most of all the long high BC 200s bullets without adding to much addition barrel torque when shooting. Definitely no less than a 10t rate. In either a standard 6 or 4 groove configuration.[/QU

This is the only way to go the 185 gr Berger Juggernauts bullets are thing of past with the new 700+BC of New Sierras and the Jacks from KP Balistics well said 308 Bar
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I have a JC 308 1:10.33 6 groove barrel, that barrel shoots everything, went up to 220's but I didn't see the advantage.
Currently using one of his regular 10 twist 4G to shoot 155's, super accurate.
 
manitou210 said:
This is the only way to go the 185 gr Berger Juggernauts bullets are thing of past with the new 700+BC of New Sierras and the Jacks from KP Balistics well said 308 Bar
Click to expand...

Agreed... 185 gr Berger Juggernauts have been the go to staple for FTR for years with the occasional ambitious sort testing heavier things. Sooner or later the heavy round testers would collectively strike pay dirt.

You will still be on solid ground with the 185s, but to compete with the best, you'll need to master the 200s as well.

If I could suggest a 50-50 approach where you hybridize a little... throat the chamber short enough that you can still run the 185 jug, (seated maybe .150 into the neck) but make sure you have enough twist rate for the 200 grainers. The seating depth might be a tad shy of what would be ideal for the powder capacity for 200's but it will be close enough. I would probably suggest the 9.5 twist so you can stabilize without running a brass crushing load.... just spin a little faster than the 1:10.

If you decide to commit to the 200s you can always have the throat extended to idealize case capacity for the 200s. Barrels don't live long in F Class anyway.
 
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The key thing is to know the optimal throating length for the 30cal bullet you choose to shoot. Unfortunately one freebore length is not a good fit for all FTR 308 bullets. If you choose the Jacks or the new Sierra 200s for example (or any short bearing surface, long nose, high BC bullet design), you need to run a shorter freebore, between 0.110”-0.125”. If you try to run it in A 2013 FTR throat 0.170" FB with a short bearing surface bullet, you'll find that it'll be hanging on a thread with very little neck tension and you may or may not find consistency, which will be absolutely frustrating.

For the 200hyb and the 195TMK I throated it to 0.208", optimal for the 200hyb but a little less so for the 195s. With the .208" FB I find that the 195TMK's major Dia at the boatail junction is just barely seating above the neck and shoulder junction of the case. So the bearing surface is much longer on the 195TMKs. However my throat will not be able not allow me to seat a Jack or the new Sierra 200s.

So pick your pill and throat, just remember it easier to add FB length to your rifle than subtracting it.
 
TrxR the KP bullets and the new sierra 200's need a different throat and chamber than what jugs are setup for if you want them to group well and be consistent I've been trying a lot of new combinations and a 9 twist works best for those long bullets as well as a different lead angle and groove configuration
 
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