308: W748 and 150 loads

[MIAMIbaseballer]

I loaded some rds up and was surprised how early I saw signs of pressure.

308 Sig 716 and Socom 16
FC brass
Seated to cannelure (2.70ish)
Win LRM primer
150 Hornady fmjbt

At 45gr of W748 I was getting flattened primers and swipes with the Sig/ At 46gr I was getting flattened primers and swipes with the Socom 16....
Seems a little low to be getting pressure signs especially when it was about 70 degrees outside, so I'm curious what others results were using W748 and 150 bullets....

[FLIGHT762]

Gas guns will often shows pressure signs before bolt guns do.

In Hornady's 8th edition loading manual, they have a 308 Winchester "Service Rifle" section. They use a 22" M-1A for their testing. With their 155 A MAX, they show a maximum charge of 748 powder @ 45.2 grains. Pretty close to what you found in your M-1A.

I reload for 2 L/R 308 bolt guns and 2 308 L/R gas guns (SR-25 & GAP 10).

In my gas guns, I usually have to drop my loads, 1-2 grains from what I use in the bolt rifles.

[sammy]

I saw similar results with my scar 17. Using a 147g m80 the rifle likes 44 grains of 748. Primers look great, bolt cycles 100% and is very accurate.

[MIAMIbaseballer]

Ok that's what I was wondering. Thanks guys

[Fill]

Oddly enough I see this too. My go-to load for my Howa 1500 is a 150 gr SST over 45 grains of 748. Brass looks good, primers are still plenty round, and it chronos 2750-2765 fps out of the Howa. But that same load out of my VEPR .308 (basically and AKM chambered in 308) has semi-flattened primers and a very distinct 360 degree raised crater from the FP strike.

[r.harrow]

Prolly shouldn't say this, but,,,using W748 , LC cases and Win LR primers, M80 type bullets. I worked up to 47 grns. fired in a DSA58. Non-rotating bolt ofcourse, but primers were o.k. and accuracy was good. I also varied the load using different cases and CCI250 primers, no problems.