Reloading 308 for 18" dpms lr

[ooglassoo]

I have a 18" dpms lr 308 with a 1/10 bull barrel. I have atleast 3/4lb of h380 that I inherited with my complete reloading setup from my buddy whos father passed away. The setup also came with Sierra rifle reloading manual 4th ed. In this book they have these following recipes using Sierra 175gr M/K hpbt with h380 37.2gr=2200vel, 39.7gr =2300vel, 42.2gr =2400vel, 44.7gr=2500vel, 47.2gr=2600vel. So my question is would this powder work in my semi auto 308 AR? Also what load out of the five should I start with? I know there are better powders for semi auto but this is what I have on hand. Any info would be greatly appreciated.
Dennis

 

[ooglassoo]

Re: Reloading 308 for 18" dpms lr

I have a question for you guys. I reloaded 5 rounds of 308 and I used the middle load out of the 5 I had to choose from. Remington brass and 9 1/2 primer Sierra 175gr M/K hpbt with h380, 42.2gr =2400vel. The book showed coal being 2.800 I wanted to make sure it would fit the mag properly so I pressed it to 2.750. I thought about it after I finished loading that I wasn't thinking about the pressure. Do you think the 25thou would raise the pressure to an unsafe pressure? Thanks Dennis

 

[Gruff]

Re: Reloading 308 for 18" dpms lr

Pressures are actually too low. My program says 37500 psi and 89% powder burn. That's 11% of your powder going out the end of the barrel. I'd suggest BL-C2 for powder choice. Same charge would yield about 2600 fps at 49490 psi and 99.5% burn.

 

[ooglassoo]

Re: Reloading 308 for 18" dpms lr

I know there are better powders out there but I have this stuff and just want to burn it up. I was just wondering if it was safe to shoot after shortening it up the 25thou?

 

[BCP]

Re: Reloading 308 for 18" dpms lr

You're better off going to a sporting goods store and spending 20$ on a pound of varget, imr4895, win748, 4064 etc. H380 will work but it's not the best and by the time you are done with it you'll just be starting over with another powder anyways.

As far as length goes 2.75 should be okay but stick to 2.78-2.82. Nothing shorter or longer than that. Also get some PMAGS or Cproducts, if Massachusettes is a restricted state you can get mags from midwestpx that are cut down to hold 10-15 rounds instead of 20 and they work GREAT.

 

[ooglassoo]

Re: Reloading 308 for 18" dpms lr

Awesome thanks for the mag info, because yes here in MA we do have the assault weapons ban.

 

[ooglassoo]

Re: Reloading 308 for 18" dpms lr

Well I went out today with 15 reloads, I loaded 5 of each of the first loads and they all worked great. I had factory remington to sight in with then used the reloads. I notices with the reloads were shooting a little higher the factory stuff. I shot about a 2" group tho at 100yrds so there is room for improvement. I must say I'm proud of these loads it's such a gradifying experience to reload your own ammo. Thank you to all you guys who post, if it wasn't for this forum an a few others I would still be shooting all factory stuff.

 

[ooglassoo]

Re: Reloading 308 for 18" dpms lr

I loaded some more Sierra 175gr MK's with the h380 and rem 9 1/2 primers. I took my lr out and was shooting sub moa groups at 150 yrds all day. I really like that h380 so far, but I just picked up some h335 to try out. I'm trying to find a good powder that will work with my 223 bolt/AR and my 308ar. So I'm going to try the 335 see how that works for me then I'm going to try some varget. I'm hoping the 335 works because it's a little cheaper and less grains per load.