DPMS AP4 opinions

[high country]

I have an opportunity to pick up an DPMS AP4 for a good price, and have a few questions. I had originally planned to get a 24" heavy barrel model, but after handling several, I really like the handling of the AP4 with its lighter 16" barrel. Plus they just look bad a**, not that that matters...

I plan to take it out for a test shoot this weekend, but am curious about how much one really looses by the shortening of the barrel from 24 or 20 inch down to 16 inch? After handling them, 20" is as long as I would go because those 24" models are seriously heavy. It would be nice to be able to carry it further than from the truck to the bench. With surplus and/or commercial ammo, how much velocity is really lost with a 16" barrel? This gun will wear optics so sight radius isn't a factor. With reloads, could one potentially get velocity back up enough for the bullet to still be stable out at 700, 800, and 900 yards? I realize the barrel wouldn't be ideal for that sort of shooting, but could it be made up to the task if the plinking opportunity arose?

Thanks in advance for your advice!

 

[high country]

No one? I find that hard to believe...

Messing around with the ballistics calculator, it looks like some of the commercial match ammo using matchking or A-Max bullets would still be sonic at at least 800 yards. The factory specs show about 2700fps out of an unspecificed test barrel, so I guessed at 24", and gave it 50 fps per inch for an estimated muzzle velocity of 2400fps. A sierra matchking would still be going over 1200fps at 800 yards at sea level, and I am actually at about 7000 feet above sea level. I am sure there is a handload that would have that bullet going a bit faster than 2400fps out of a 16" barrel, so staying sonic to that distance shouldn't be an issue.

Other than the operator, is there another reason that 800 yards would be outside the reasonable range of the AP4? Seems like it would be a good all around option, short and light enough to carry, but legal for hunting deer and even elk (.223 isn't in CO for big game), and powerful enough to reach out for some long range targets.

 

[Omaha-BeenGlockin]

Its a DPMS ---it will be "ok"---300 yds is the practicle range you're looking at----the .223 is NOT a deer or elk cartridge--esp at extended ranges---prairie dogs maybe.

 

[TonyAngel]

Although some guys push the envelope of what the .223 is capable of, they are loading 80gr and heavier projectiles that need to be seated so far out that the rounds need to be loaded one at a time because they won't fit into a magazine.

Will a .223 shoot out to 900 yards? Certainly. Will you be able to hit anything? Maybe. In any case, if you are planning to shoot out to the distances that you mentioned, I doubt that you'll do that with any factory loaded ammunition. I also seriously doubt that you'd be doing it with a bone stock AP4.

If you want to be able to shoot that far without stretching the limits of the round, I wouldn't go smaller than a .308 and even that may be pushing it.

 

[-v-]

You all DO realize that the AP4 is a 7.62x51 rifle, right?

Yes, I think the 800-yard mark is the commonly held mark as far as maximum accuracy. With the LR308 series, 1-1.5 MOA accuracy seems to be common out of the box. Take it at what you will.

I have an 16" DPMS LR308 so....

 

[Omaha-BeenGlockin]

Looks like 5.56 to me:

http://www.dpmsinc.com/store/products/?prod=46&cat=1891

 

[-v-]

Wrong AP4, buddy. http://www.dpmsinc.com/store/products/?prod=4854&cat=1940 There's a .308 version too, which I am fairly certain he is talking about.

That said, the widely regarded maximal accurate range for a 16" bbl is 800-850 yards. If you ask me, that seems more than accurate enough for most any shot you might take. I have also been looking for some hot .308 loads, but nothing I've seen posted pushes it to the 1000 yard mark, so far.

 

[dhfenno]

I have 2 LR308AP4s and love them. One lives in TX where I hunt and one in MD where I live and do most of my shooting. DPMS uses a 1in 10 twist which works well to stabilize a heavy bullet. The twist rate loves a 168 or above grain bullet. I have MOA accuracy out of the MD gun with a 175gr SMK pushed by 43gr of RL15. I get even better with a 180 grain Sierra Pro Hunter over 42gr of RL15. Both rounds are loaded to 2.80 OAL. Like all loads start lower and work your way up to see what your rifle shoots best and always check for signs of excessive pressure.
Both rifles wear a variable scope up to 14x. I originally had a 3x9x40 on the TX gun but quickly discovered I could use more glass and really stretch my range.

 

[high country]

Thanks all for the replies. Yes, this is a 7.62x51 chambered AP4.

I got it out for a short test "drive" yesterday, and wow, what an incredible rifle. It ate surplus, white box, and federal match without a hitch. I only had about 200 yards to work with where I was, and no bench, but I was able to ring an 8" plate with regularity using the sling with all three of those rounds. I got the sense that that is where this gun really shines--unsupported shooting at mid range. But, it is great to know that in one gun, you can have a short length fast handling carbine, that balances nicely for offhand shooting, but that can still reach out up to 800 yards with the right ammo.

The prior owner had a cowitness set up that has a 2-7x scope on top and the irons that sight through underneath. It makes the scope pretty much worthless because it is waaay to high. I think that I am going to go with a higher power scope on a quick release mount and a flip up rear sight. And it really needs a trigger upgrade. Then, track down the load that this thing really likes (thanks for the suggestions on that dhfenno), and go to a range with a lot more space.