powder suggestions and findings…rem 700 aac-sd 20" aics 1.5 stock

[thechristianbear2001]

I have been playing with my rem 700 aac-sd 20" for a few weeks now after finding some imr 4064. I have been getting decent, but definitely not great groups with charges around 42.2grs. I would have a .75 group but usually get a flyer that opens it up over a inch. I have played all around with it and the groups just get worse. Then, on a whim because my buddy micah had some winchester w760 we loaded up the low load 44.0 grains and I fired a sub moa group at a 100. Played with it yesterday and at 44.5 the 5 shot group measure .79 on the calipers. Had one group going that I think would have been close to .50 but got a "flyer" still touching the other bullet holes but out a little further. So apparently my gun likes the winchester powder better than the imr stuff so far. Still would like to try varget and r-15 if I can ever find it because I have heard the winchester stuff doesn't do well past 600yds. In any case, are my thoughts and findings similar to anyone else?

Shooting 175gr sierra matchkings, most measure 2.800 with fed 210 primers and lapua brass

 

[korykhunter]

Check gunbot for powder, you may find some there.

 

[ptaylortx]

My aac-sd will shoot .75" seated .010"off the lands but with Remington's huge amount of free bore in their chambers, they are way past mag length. I could not get better than 1" inside mag length with most groups in the 2"range. I've spent half the cost of a barrel on powders and bullets and have gotten nowhere even with an HS stock and timney trigger. I've given up and It's being re barreled now.

 

[thechristianbear2001]

What barrel did you go with?

 

[Brux]

Might try playing with some seating depths.4064 is a great powder for 308.JMO

 

[givey]

I have a newer AAC-SD, about 125 rds through the gun now. 41.7 grns of IMR4064 (MK316 MOD CLONE), LC LR brass shoots consistant 5 shot groups under and inch. Its not the fastest load but most groups are under .6". RE 15 43-44.4 grains and Lapua Brass are consistant groups under .5" (these are over Sierra's max so start low and work your way up. I seat this to 2.81 so the will fit in the mag, the jump does not seem to affect accuracy.

 

[he lives]

I've only been reloading for about a year now, but had a couple thoughts you might find helpful.

First, how many rounds have been through the rifle? I just ask to see if it's been broken in at all.

Second, I can't tell from your original post, but it seems you may be choosing charge weights and trying them out to see how each one works. I think youd be better off to shoot an OCW or Ladder test. Go shoot a test with a whole range of charge weights under the same shooting conditions and post your results. There are a lot of experienced reloaders here that could give you advice based on your results.

 

[Dan Newberry]

If you really want to use the 760, work on up to 47 to 48 grains, per Sierra's max load data. Then you'll get enough velocity to make good long range shots. It should be running close to 2600 fps at that point anyway. The 44 grain charge from a 20" barrel very likely has you in the 2300 fps range--if that.

You don't mention your brass, but your selected charge of 42.2 grains sounds like Sierra's accuracy load. Brass is very important to the recipe, however. With Winchester brass (I know Sierra says they used Federal brass but that's not an OCW load if they did)... but with Winchester brass, the 42.2 grain charge is about right. With Federal or Lake City or average military brass, 41.8 would be closer to where you want to be.

There is nothing wrong with using a ball powder for long range work, but you do have to learn its quirks, and adjust for them. I recently noted a 1 MOA drop in elevation on my 308 at 1040 yards in a temperature drop from 50 degrees to 40 degree with w748 as the powder. But even though the elevation changed, accuracy held strong, with vertical spread well under MOA at that distance.

That all said, the 4064 will still serve you better in the long run. It's really the 308 powder by which all others are judged, and it didn't come by that reputation undeservedly. Just find the right charge for whatever brass you're using, and accuracy should be there.

Dan

 

[ptaylortx]

Bear, I went with a Hart 22" rem contour .920"@the muzzle. I've had real good luck with them and they have a lot quicker turnaround.

 

[thechristianbear2001]

nice…. I would love to hear how it shoots when you get it all set up and have time to play with it

 

[thechristianbear2001]

I've only been reloading for about a year now, but had a couple thoughts you might find helpful.

First, how many rounds have been through the rifle? I just ask to see if it's been broken in at all.

Second, I can't tell from your original post, but it seems you may be choosing charge weights and trying them out to see how each one works. I think youd be better off to shoot an OCW or Ladder test. Go shoot a test with a whole range of charge weights under the same shooting conditions and post your results. There are a lot of experienced reloaders here that could give you advice based on your results.

I have over 400rds through it now….. when I reload I usually make 5-7 rows of 5 shells. Each row has a different charge weight and then go and shoot them at 100yds. I circle the group and include all the data. I am not sure how else to do it as I have never heard of the tests you inquired about. Thanks for the reply my friend---

If you really want to use the 760, work on up to 47 to 48 grains, per Sierra's max load data. Then you'll get enough velocity to make good long range shots. It should be running close to 2600 fps at that point anyway. The 44 grain charge from a 20" barrel very likely has you in the 2300 fps range--if that.

You don't mention your brass, but your selected charge of 42.2 grains sounds like Sierra's accuracy load. Brass is very important to the recipe, however. With Winchester brass (I know Sierra says they used Federal brass but that's not an OCW load if they did)... but with Winchester brass, the 42.2 grain charge is about right. With Federal or Lake City or average military brass, 41.8 would be closer to where you want to be.

There is nothing wrong with using a ball powder for long range work, but you do have to learn its quirks, and adjust for them. I recently noted a 1 MOA drop in elevation on my 308 at 1040 yards in a temperature drop from 50 degrees to 40 degree with w748 as the powder. But even though the elevation changed, accuracy held strong, with vertical spread well under MOA at that distance.

That all said, the 4064 will still serve you better in the long run. It's really the 308 powder by which all others are judged, and it didn't come by that reputation undeservedly. Just find the right charge for whatever brass you're using, and accuracy should be there.

Dan

Been using the lapua brass so far….




Thank you everyone for your responses so far…..much obliged

 

[he lives]

The OCW Test is from Dan Newberry who actually commented on your post already. I've had good luck using it in load development. Sounds like you may be doing something similar already.

Here's a link to his site and it explains the OCW Test.

OCW Overview - Dan Newberry's OCW Load Development System

 

[thechristianbear2001]

The OCW Test is from Dan Newberry who actually commented on your post already. I've had good luck using it in load development. Sounds like you may be doing something similar already.

Here's a link to his site and it explains the OCW Test.

OCW Overview - Dan Newberry's OCW Load Development System

will check it out--- thanks

 

[stang_j_99]

Im running a 700 sps Tac w/20" barrel. honestly, 39.5 grns of imr 4064 was the most accurate load (.225) but not fast enough for me at somthing like 2200. 42.5-44.0 tightend back up at around .3". Using 168 berger hunting vld's. IIRC seating was 2.250 ogive.