Home Forums Hunting & Shooting AR and Tactical Rifles Best long range 223 load at mag length

What Iv'e heard has been the same, SMK stil more accurate by far than TMK.

Jeff, I'll bet your old 75 AMAX loads were better. (But still no Grendel killer)

nope. No grendel killer.

There always has been a differnece at times, IMHO, in what a book, ballistic program, BC, or chrono says and what you see in real life shooting real distances....

Fooled around some with a 1 in 9" .223. The 77 TMK was around MOA or so. The Berger 77 OTM did much better, and is a bit shorter bullet. I'm going to try it in a 1 in 7" Mk12

I bought three of the ASC mags, which allow an OAL up to about 2.31". Will try some 75gr Amax and other bullets, to see how they shoot.

They are shooting good for me in my BCM. Burned up 1k and got another 1k loaded. Using max load of TAC and a CCI BR primer.

What do you consider good?

You can do it safely today with CFE 223, I run 25.6 gr in my 18 1/2 inch Wylde chambered AR, am getting 2710, Hornady lists 26.5 as max with their 75 gr A max. I am also getting 2685 with 24.5 gr RL 15 with the 77 gr Nosler Custom competiton bullet.

Which ASC mag to order? To give you max length?

http://gunmagwarehouse.com/brands/asc

And how many shots.

The stainless mags:

http://www.ammosc.com/223-stainless-steel-20-rd-magazine/

ASC Stainless Steel magazines are an improvement on a classic, with the highest levels of durability and increased longevity, simply the best in the industry! Our magazines are manufactured 100% start to finish in the USA using .020 gauge 410 Stainless Steel Alloy, heat treated for superior strength and lasting endurance. Our magazines are chemically treated for corrosion resistance [ref QQ-P-35] and coated with our proprietary finish, Marlube which is a wear-in not wear-off coating that burnishes into the surface providing self-lubricating properties. The interior dimensions of OAL 2.316” ± .002 are perfect for reloads.

That's the one I ordered, thanks.

Tried a little experiment I read about, cut a slot front of
plastic 20 round mag, and got 75 GR A Max to fit and feed in my Bushmaster at 2.48" OAL.

hmm.. wonder how many years ago they started cutting fronts out of mags.

LOL

The true tested BC of the Amax and SST is not 510. That is Hornadys published BC but it has been proven wrong. We are shooting the loads I said and getting the velocities I said shooting 3 different Grendels and 4 5.56s side by side. .020" freebore doesn't make any difference in pressure because the bullets aren't stuffed into the lands.
My Iphone with AB program died so we started using an I pad and JBMs program online. The stupid thing works off their sever and changes the numbers as it finishes loading. At 300 yds the 77TMK is flatter than the 123, we can see that. We are working up loads at 300 to make sure we have the fastest accurate loads before we travel 2 hrs to the closest 1000yd range. Jeff and Bill were back out there today but i haven't heard anything. None of us plan to shoot more than 600 with these rifles, all of us have other rifles better suited for 600.
On another note have any of you tried the Beger 80gr Fullbore bullets in an AR loaded to mag length(2.28)?

Glad to see you are getting the velocity we are. The Wylde chamber doesn't shoot the TMKs as tight as we want them but the shorter throat works well when we load them out to 2.28 in metal mags. For accuracy work we stopped using mapul mags a few years ago.

10-shot groups under 2 moa. Not bolt gun accuracy by any means, but the same rifle shoots 53gr V-Max 1 moa or better with the same powder and primer.

Tag

Says about the bullet what I've heard...

If you shoot the TMK in a Wylde or 556 chamber loaded to 2.26 to fit in magpul mags the accuracy is not there. If they are loaded out to 2.3 and used in a Wylde the accuracy can be good or if they are loaded to 2.28 and used in a chamber with a freebore of around .040 instead of .061 they will shoot. We always look for 1/2MOA but sometimes settle on 5/8 or 3/4.

Shot some groups earlier today using 26 gr cfe 223 and the 69 gr tmk, pathetic, best group was about five inches, don't know why but cfe 223 and the tmk's don't work well, had good luck with AA2460, A2230 and exterminator.

I checked out the ASC site and saw that they make OEM mags for several manufacturers. Got me thinking...I have several different brand mags, plastic, steel and aluminum.
Got out the calipers and did some checking on the OAL possible with each.

Pmag plastic - 2.266"
Wilson Thermold plastic - 2.274"
Bushmaster Stainless - 2.313"
AR Stoner Stainless - 2.310"
Colt Aluminum - 2.264"

So, I think I will load up some 2.3" OAL loads and give em a try.
Always thought I was limited to 2.26"