.308 IMR4895 Load Development

[grfox92]

Hey guys, new reloader here. I have been working on a load for my .308 with 168gr ELD-M.

I tried every increment of powder from 42.5gr up to 44gr which is book max for IMR4895 and 168gr.

The gun like 43.5gr best, but I'm still not happy with the groups. Everything I've loaded has been to book COAL of 2.80.

I've decided to start playing with seating depth and see how they shoot. I figure I'll jump right to 2.90, as long as they fit in the magazine, and see how they shoot.

My question is, and I know some might be reluctant to give advice outside of book numbers but I was thinking about starting with 44.1, 44.4, 44.7 and up to 45 gr of IMR 4895.

Has anyone worked up a load with this combo or similar? Am I asking for trouble with 45gr? It's Remmington Peter's brass.

4895 is the only powder I have right now so it's what I've got. If I'm not happy with grouping after playing with seating depth I'll buy and try a different combo. The rifle is a Ruger American Predator.

Thanks for any help,

Gary



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[Vern400]

I've never used that powder. But if you're doing a test on seating depth, forget mag length completely. I wouldn't recommend jamming the bullet even though sometimes it shoots good. Pull it back 0.010 to 0.020 off the lands and see what happens. Your gun probably has 0.1 to 0.15 inch of jump as you've got it loaded. Don't drive yourself crazy with statistically irrelevant changes. It either works or doesn't. I've cut groups in half doing that. If you can't get the performance you want within the mag length, you might have to pick a bullet to get you closer to the lands at mag length like Sierra 2125s or 2140s. If your gun won't shoot one of those two bullets well, my guess is that it won't shoot. Love them or hate them, most people that have tried Sierra SBTs say it's relatively easy to get them to shoot well out of a 308 or a 6.5 ( different part numbers of course).

You sound like you might be a new reloader to 308. I don't mean to sound disrespectful so don't slam me. But cleaning your gun can really screw you up. My 7.62 bolt guns take three to five shots to get back on zero after cleaning and they're polished machines with anywhere from 1,000 to 4000 rounds down the pipe. Some newer barrels on factory rifles take even more shots to start grouping again. Make sure your rifle is clean enough to be healthy, and dirty enough to be happy!

 

[grfox92]

I don't have a way to find the lands. I know the Alex Wheeler method of taking the firing pin and extractor out and checking for bolt flop, but I'm not there yet and was just going to see how it shoots seating further out.

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[Sccritterkiller]

I use that powder for 180 NP in my 308..my best groupings are around 39.5.
It's 308 try a different powder, 3031, varget, ect. Those Rugers have a 18" barrel IIRC? So you may have to do some testing to find the best load. My 18" 308 with a can really likes 150gr bullets and 3031...YMMV

 

[Vern400]

I don't have a way to find the lands. I know the Alex Wheeler method of taking the firing pin and extractor out and checking for bolt flop, but I'm not there yet and was just going to see how it shoots seating further out.

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You do have a way to find the lands. Load one empty resized case with a bullet at 2.95 oal. Smoke the bullet with a candle and shove it in the hole. If the bolt won't shut seat the bullet a little deeper. When you get it right you should be able to see rifling marks. Just little tick marks. Back off 0.010 and shoot it. ( Ones with powder). At the end of the day it doesn't matter whether you have the fancy tool, or whether you use a process with some dude's name on it. But if you're going to run a seating depth test go straight to the longest length that will fit because for a whole lot of 308 rifles that's their happy place.

 

[grfox92]

I use that powder for 180 NP in my 308..my best groupings are around 39.5.
It's 308 try a different powder, 3031, varget, ect. Those Rugers have a 18" barrel IIRC? So you may have to do some testing to find the best load. My 18" 308 with a can really likes 150gr bullets and 3031...YMMV

Thanks. Mine has a 22" barrel. Like I said I will try different powder in the future. I'm just trying to find a combo that works best with what I have for now.


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[Windigo]

Hey guys, new reloader here. I have been working on a load for my .308 with 168gr ELD-M.

I tried every increment of powder from 42.5gr up to 44gr which is book max for IMR4895 and 168gr.

The gun like 43.5gr best, but I'm still not happy with the groups. Everything I've loaded has been to book COAL of 2.80.

I've decided to start playing with seating depth and see how they shoot. I figure I'll jump right to 2.90, as long as they fit in the magazine, and see how they shoot.

My question is, and I know some might be reluctant to give advice outside of book numbers but I was thinking about starting with 44.1, 44.4, 44.7 and up to 45 gr of IMR 4895.

Has anyone worked up a load with this combo or similar? Am I asking for trouble with 45gr? It's Remmington Peter's brass.

4895 is the only powder I have right now so it's what I've got. If I'm not happy with grouping after playing with seating depth I'll buy and try a different combo. The rifle is a Ruger American Predator.

Thanks for any help,

Gary



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Hey man, I've had the same problem with VLD style bullets in my 308 Predator. Try the berger seating depth method, but you might find yourself limited by the mag length. I've had best success with more "traditional" bullets, like the smk. Currently working on 165gr Swift Sciroccos and H4895 out of a RAP, so I know what you're going through.

Getting the Best Precision and Accuracy from VLD bullets in Your Rifle

VLD bullets are designed with a secant ogive. This ogive shape allows bullets to be more efficient in flight (retain more velocity = less drop and wind deflection). While this result is desirable for many rifle shooters the secant ogive on the VLD bullets produces another result in many rifle.

bergerbullets.com

 

[49ereric]

Try a different bullet (150’s-180‘s) if changing the seating depths doesn’t work.
to often people want to shoot a specific bullet-weight these days when we always let the barrel decide decades ago.

 

[grfox92]

Try a different bullet (150’s-180‘s) if changing the seating depths doesn’t work.
to often people want to shoot a specific bullet-weight these days when we always let the barrel decide decades ago.

Yea I'm totally open to different bullets. I want to try the Bergers like recommended above.

Unfortunately all I can get out of the factory magazine is 2.841. That really sucks and didn't realize it would be an issue with this rifle.

I'll load some at 2.90 and shoot them single shot. If it drives tacks I can upgrade the magazine.

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