Gas gun .308 powders

[markm]

I walked into Shipton's Big R and they had a pound of IMR 4061. Looks like I'll be loading some of that.

A buddy and I were texting yesterday. His sweet spot is 44.0 gr with the 155 TMK. But with 4064, the lot swings are big. He had a 70+ fps swing. I'm going to test a load starting at 43.0 and maybe 43.5.

[czgunner]

A buddy and I were texting yesterday. His sweet spot is 44.0 gr with the 155 TMK. But with 4064, the lot swings are big. He had a 70+ fps swing. I'm going to test a load starting at 43.0 and maybe 43.5.

Interesting. I watched a video (Johnny's reloading bench), and he mentioned that FGMM changed from RL15 to IMR 4064 to get more temp stability. Is it more lot sensitive than most? Oh well, I'll burn through this pound and see what it does. Thanks for the constant helpful input.

ETA: He starts talking about it around 4:36 https://www.youtube.com/watch?v=GEOQATHtKS0

[Pappabear]

Interesting. I watched a video (Johnny's reloading bench), and he mentioned that FGMM changed from RL15 to IMR 4064 to get more temp stability. Is it more lot sensitive than most? Oh well, I'll burn through this pound and see what it does. Thanks for the constant helpful input.

Sent from my Pixel 3 using Tapatalk

That is very interesting if it's true. We have a fair amount of 4064 and generally only use for gassers. But FGMM is legit and always shoots nicely. I'm excited to see what we get out of my Bolt gun with the 155's velocity wise because our buddy shoots them out off his 13.5 Scar. I hope they are smoking pretty good. Minus trashing brass and popping primers.

PB

[markm]

he mentioned that FGMM changed from RL15 to IMR 4064 to get more temp stability. Is it more lot sensitive than most?

RL-15 was horribly temp sensitive than 4064 in the military tests for the 7.62 LR ammo. I have no idea why they still went with it. It wasn't even close.

4064 does have some lot to lot swings in velocity in my experience. Anymore these days, you can't buy just 1lb of powder and run it. If you can't get at least 5-8 lbs of a given rifle powder, forget it.

[2ndtimer]

I have had decent results with TAC in my PA-10 using the Speer 125 gr TNT bullets (cheap and accurate). IMR-4064 is what I run with 168 gr Nosler BTHP’s in my bolt gun. I just scored some factory IMI 175 gr OTM ammo from Midway and plan to try some tomorrow in both to see if it might be worthwhile to try some heavier bullets. My attempts with TAC and heavier (150 - 168 gr) in the gas gun weren’t great, but I haven’t really tried IMR-4064 in it yet.

[Pappabear]

4064 should treat you just fine with heavier bullets. Better powder in general. Good luck.

PB

[markm]

The only downside with 4064 is the kernels are long cut rice. I tried running it once in my Dillon 550b and it was a mess. Chargemaster only for me with 4064.

[308TRUMPFTW]

I have had decent results with TAC in my PA-10 using the Speer 125 gr TNT bullets (cheap and accurate). IMR-4064 is what I run with 168 gr Nosler BTHP’s in my bolt gun. I just scored some factory IMI 175 gr OTM ammo from Midway and plan to try some tomorrow in both to see if it might be worthwhile to try some heavier bullets. My attempts with TAC and heavier (150 - 168 gr) in the gas gun weren’t great, but I haven’t really tried IMR-4064 in it yet.

TAC works fine in 308. I load 42 grains of it in military brass with 150 grain hornady bullets. Varget and 4064 are better though.

[m1a_scoutguy]

Hard to find I would think but in my M1a I used and loved IMR 4895 ! 42 grns and a 168 Nosler or Sierra and it always shot sub-MOA in my Fulton NM. AR style could be different I'm sure.

[mark5pt56]

Pretty sure the latest batches have been 4064, for some years now.

RL-15 was horribly temp sensitive than 4064 in the military tests for the 7.62 LR ammo. I have no idea why they still went with it. It wasn't even close.

4064 does have some lot to lot swings in velocity in my experience. Anymore these days, you can't buy just 1lb of powder and run it. If you can't get at least 5-8 lbs of a given rifle powder, forget it.