H4895 with 200.20x

[APGE]

Hi Folks,

Could someone give me a ballpark for what charge weight a 308 should come into tune at the 2680ish mark with H4895 and 200.20x? I've read around 43.0, but would like to confirm this.

I'm hoping to shortcut some load development by getting an idea of roughly where I should end up.

Freebore is 0.180" and barrel is a 32" Brux.

Thanks gentlemen

 

[swadiver]

Large or small primer Lapua brass?

 

[Ned Ludd]

30" barrel
0.180" fb chamber
COAL = 3.114" (~.012" off the lands)
Lapua Palma (SRP) brass
Temp = ~85 degrees F

42.8 gr H4895 = 2657 fps avg.
42.9 gr H4895 = 2668 fps avg.
43.0 gr H4895 = 2674 fps avg.

You might observe a tick higher velocity with a tuned load on a per charge weight basis with 2" more barrel length, maybe as much 10-20 fps, but probably no more than that.

After shooting the 42.8/42.9 gr loads at a few matches, I eventually worked up a load with the 200.20Xs and Varget and have never regretted the switch. The 200.20Xs with Varget tuned in a tick slower (~2640-2650 fps) than with H4895. However, I found the recoil impulse with H4895 to be more like a sharp "crack", whereas the with Varget, it is more like a gentle "push". Although in my hands the precision was comparable with both powders, I find shooting the Varget load to be just a bit easier. For only an additional 15-20 fps, the difference in recoil over the course of 60+ rounds, it just didn't seem worth it to load with H4895. In my opinion, H4895 is just a bit too fast for a 200 gr bullet in the .308 Win. However, I know a few shooters that have used the H4895/200.20X combination with outstanding results. For me, the difference in recoil with H4895 is not a pain or discomfort issue of any sort, the recoil of a .308 with 200s simply isn't that severe. However, it does seem to require more careful attention to gun handling, so it's just an added distraction I'd rather not have. YMMV. Hope this is helpful.

 

[Baddog0302]

Ned
With the lower Wt. bullets a general rule of thumb is + .5 to 1 gn, of Varget from an H 4895 load. Did you find that so with the heavies 190 + gn bullets?

 

[Ned Ludd]

Ned
With the lower Wt. bullets a general rule of thumb is + .5 to 1 gn, of Varget from an H 4895 load. Did you find that so with the heavies 190 + gn bullets?

Yes. I can imagine there might be an exception to that once in a rare while, depending on freebore length and bullet dimensions/weights. But in my hands, one half to a full grain less H4895 as compared to Varget is generally what I've found in both .223 Rem and .308 Win loads, with a variety of different bullets. My go to Varget load with the 200.20X bullet is 43.5 gr, which gives ~2650 fps in two similar F-TR rifles with 30" barrels. So the Varget load with the 200.20X has 0.6 to 0.7 gr more powder as compared to the 42.8/42.9 gr H4895 load I mentioned above.

 

[Joe Wade]

Hi Folks,

Could someone give me a ballpark for what charge weight a 308 should come into tune at the 2680ish mark with H4895 and 200.20x? I've read around 43.0, but would like to confirm this.

I'm hoping to shortcut some load development by getting an idea of roughly where I should end up.

Freebore is 0.180" and barrel is a 32" Brux.

Thanks gentlemen

My experience with H4895:
You are right in there for H4895 powder and My Free Bore of .160". Shooting Berger 200.20x bullets with Palma brass and 28", 30" and 32" Bartein barrels with 42.5-43.3 grains depending on barrel tune. Should achieve velocities of 2580's to 2640's. I only had one 32" barrel and could not get the accuracy I wanted until I cut off 2". I think 2680fps is right on the edge of max pressure and started to see loose primers and brass cracking at .200" line. I would suggest finding the best accuracy that 2580-2640fps will offer in your barrel and have fun winning. The extra 50 fps will likely cost much frustration. I always tune to best accuracy, even if it is only at 2580fps. I personally favored H4895 over Varget in 308 for F-tr. YRMV. For best results, compare different lots of H4895, some are much better than others. Just my experiences and 5 state championships. Good Shooting.