What COAL for AR?
- Thread starter Matty308
- Start date
You are screwed because the 75gr A-MAX #22792 has a C.O.L. Of 2.390" and is intended for single loading.
In the Hornady manual it says "This bullet cannot be loaded to magazine length. The Hornady 75gr A-MAX bullet is an excellent choice over 600 yard ranges in single shot shooting."
Ask me how I know :-(
You need the #2278 68gr BTHP or the #2279 75gr BTHP which both load to a C.O.L. of 2.250".
I load my AR .223 to 2.24 +/- and they feed and fire fine. I use Vmax or Zmax 50 or 55 gr mostly.
I tried a box of 75 gr Amax for my Rem 700 5R and I couldn't even seat them to the 2.26 that I use for that gun. The Amax is so long I had to screw my Lee seating die in so far that I hit the end of the thread trying to get to 2.26.
I tried a box of 75 gr Amax for my Rem 700 5R and I couldn't even seat them to the 2.26 that I use for that gun. The Amax is so long I had to screw my Lee seating die in so far that I hit the end of the thread trying to get to 2.26.
The mag will be the limiting factor. So whatever max length will fit and feed in your mags.
I have only had this problem with 75gr Amax. I have used 75gr Match bthp and they seat just fine. Gotta be the fact that the Amax have a pointy little tip that's longer than the hollow (presumably chopped off) tip on the Match bthps
It is the profile of the Amax ogive that is the problem, it is very long and pointy. To load them to 2.250" means the ogive starts down inside the case neck, leaving an edge to catch while feeding. There are other 75+gr bullets with a shorter ogive that work fine when loaded to AR mag length.
Mark
I know! I know! just bust that little red tip off and now you got really heavy match grade hollow points! although with a slightly lower BC. but that's ok, i don't think the zombies will know the difference. that is why we buy ARs right?...for zombies.....right?
Does yours look like little SR-71 engines? lol
What's your powder & powder weight? If the powder weight was close to max, I personally would pull 'em but I'm chicken like that with reloading.
My concern is that you risk the bullet getting slammed into the case when the rifle is cycling. Not sure if that's enough to cause a KABOOM situation.
For cheap decent plinking ammo, I use Hornady 55gr FMJ w/ cannelure. They're about $13/100.
For cheap decent plinking ammo, I use Hornady 55gr FMJ w/ cannelure. They're about $13/100.
Well I have shot probably between 50 and 75 of them with no issue, not to say that it can't happen and now I am ever more skeptical. Do you think that's the only risk? The reason I wanted some heavier grain bullets is because my rifle barrel is 1/7 twist, and apparently work better with heavier grain bullets. I am upset now because I just made up like 170 rounds and have half a box of Amax left, don't know what to do..
The 75gr. AMax has a shorter bearing length than a 69 gr. SMK, and will work fine in most 9 twists as the bearing length is really what drives whether a bullet will work with a given twist.
Those rounds seated to 2.260" or shorter - they may feed fine, but you are courting bullet setback, and a potentially unsafe situation. Add to that the fact the AMax has a secant ogive, and with that OAL, a hellish long jump to the lands - they are probably not giving you the accuracy you want at shorter ranges, and at longer ranges, the likelihood of concentricity issues creeping in are quite likely.
They really are designed for hand loaders a) loading into or nearly into the rifling lands, and b) single loading their ammo or have mags (on bolt guns) that can handle longer OAL.
There are other excellent (and arguably better) bullets that work in the AR - 77gr. SMK, Nosler 77 gr. OTM, the new (in 2014-15) Sierra 77gr. Plastic tipped match, Berger 77LTB & 73 gr. BT match bullets are just a few.
Those rounds seated to 2.260" or shorter - they may feed fine, but you are courting bullet setback, and a potentially unsafe situation. Add to that the fact the AMax has a secant ogive, and with that OAL, a hellish long jump to the lands - they are probably not giving you the accuracy you want at shorter ranges, and at longer ranges, the likelihood of concentricity issues creeping in are quite likely.
They really are designed for hand loaders a) loading into or nearly into the rifling lands, and b) single loading their ammo or have mags (on bolt guns) that can handle longer OAL.
There are other excellent (and arguably better) bullets that work in the AR - 77gr. SMK, Nosler 77 gr. OTM, the new (in 2014-15) Sierra 77gr. Plastic tipped match, Berger 77LTB & 73 gr. BT match bullets are just a few.
Here is a pic of what they look like.
Wow...that looks weird. I load the Amax to 2.52" COAL. They are only a little shorter than some of my 308 rounds...LOL.
Mind you, mine are being single loaded in a 1:7 twist bolt action. With a COAL that short I'd be a little concerned about over pressure due to compressed powder loads. Do you feel the powder crunching when you seat your bullets?
