ive got a armalite ar-10 in 308... it's easy to shoot, and ive got quite a bit on ammunition... but ive also got a lot of .243 Winchester...since all the "craze" is still going on, ive have an upper ordered from armalite over a year.. and no delivery date in sight...so I figure to build 1... I can use the bolt from the .308, but need another upper and barrel... I want a stainless bull bbl, 20"... where do I start looking??... thanks, jim

Just curious...

Why an upper in 243???

What is it FOR???

quote:

Originally posted by N E 450 No2:
Just curious...

Why an upper in 243???

What is it FOR???

Simple...its for someone that found a SHITLOAD of 243 ammo for SUPER CHEAP and wants to have fun shootin' it!

Right Jim?

You have to make sure the upper receiver will fit the ArmaLite lower. ArmaLite's lower corner of the upper are slanted instead of round. I believe you can put a DPMS upper on it, but there will be a gap where the corner I'm speaking meet.The head space on Armalite is different if you use another brand manufacture barrel with your ArmaLite bolt. In other words get a 243 barrel built for an ArmaLite. Many ArmaLite parts are interchangeable with other AR10 type rifles, but you shouldn't be mix matching bolts and barrels. The gas tube on the ArmaLite is also longer then say DPMS.

Now the reason for 243 upper would be that most heavy barrel AR's outshoot a good many bolt rifle and are not affected as much by weather/humidity and temperature changes as long as they have a free float front forearm.

+1 Andy & J .... ive got 2 other .243, 1 is a pushfeed m70 and the other a hi-grade BAR... I like the AR profiles...and a 20-24" heavy bull with a twist for somelight bullets would be fun... plus ive got about 4k brass, maybe that many bullets in different weights.... ive got room in the safe, and money to pay for it... good enough???

I like the 243 round, in fact my pig culling rifle is 243 and has been used on several hundred hogs over the years. Now the problem is the 243 is a barrel burner because all of the powder does not burn inside the cartridge. So you have a 1250 degree torch in you barrel every time you shoot. It is bad enough in a bolt gun but I can see accuracy in your ar dropping off pretty quick maybe. I still love the idea though. Just be prepared to buy a new barrel about once a year depending on how much you shoot.

quote:

Originally posted by Mike Smith:
I like the 243 round, in fact my pig culling rifle is 243 and has been used on several hundred hogs over the years. Now the problem is the 243 is a barrel burner because all of the powder does not burn inside the cartridge. So you have a 1250 degree torch in you barrel every time you shoot. It is bad enough in a bolt gun but I can see accuracy in your ar dropping off pretty quick maybe. I still love the idea though. Just be prepared to buy a new barrel about once a year depending on how much you shoot.

Why would there be an accuracy drop off on the AR barrel over a bolt action? I'm not buying that. If you reply because it's semi auto and there is rapid firing, you'd be wrong. It's still an hunting rifle. Most quality barrels on AR's are stainless steel too. Too much BS and myths about AR's. I also don't see the 243 as a big barrel burner.

No it is because a gas operated system has many more factors affecting accuracy up to and including even the magazines. It is a finely tuned system that can be thrown off by slight variations. As for the barrel burner part do some research on the cartridge. If you don't shoot but a few rounds here or there it will not matter but in a serious working rifle it will be a different story. That is the same bolt or semi auto.

I figure that I might shoot 4000 rounds thru it.... im not interested in a burning load, but an accurate one....

GAPrecision.net.

I could make a barrel for you, but good luck finding the stripped upper, I'd like to find another one myself. And as for DPMS vs. Armalite, the DPMS upper will not fit on an Armalite lower. The Armalite will fit a DPMS but will leave a gap at the rear.

quote:

Originally posted by Mike Smith:
No it is because a gas operated system has many more factors affecting accuracy up to and including even the magazines. It is a finely tuned system that can be thrown off by slight variations. As for the barrel burner part do some research on the cartridge. If you don't shoot but a few rounds here or there it will not matter but in a serious working rifle it will be a different story. That is the same bolt or semi auto.

If it was a gas piston system on the AR's I would agree with you, but with direct impingement there is no disturbing the bullet. The gas tube going back to the receiver is free floating and only anchored at the gas block by a tight fit and pin. The receiver end is floating and the carrier key surrounds. By the time the gas gets inside the carrier and reacts on the piston end of the bolt the bullet is long gone from the barrel. AR's can be VERY accurate. I would doubt, except for professional bench rest shooter that most shooters wouldn't see the difference. The piston operated AR on the other hand can't complete with the direct impingement in accuracy. Too much more weight on top the barrel and too much more reaction happening with the piston rod movement. I know I said by the time the gas got to the inside of the carrier the bullet would be gone, but remember the on the piston system the piston is right there at the gas port. It's going to react as soon as the base of the bullet passes the gas port.

You shoot just about any high velocity barrel a lot and you're going to wear it out. I personally haven't heard the varmint shooters complain about barrel wear in a 243.

I doubt the varmint guys are shooting 20k rounds a season either. As I said earlier even switching mags can open up your group size. That is why serious high power competitors test a lot of different mags and mark the best ones. There are just a lot of factors in a gas operated system that can affect your group size. Now the difference isn't huge, but an extra one inch spread in your group can be all the difference between winning and loosing especially at the longer ranges. I think you and I are actually on the same page we just are not (or at least I am not) being concise enough. We are basically in agreement but looking at it from 2 different perspectives.

quote:

Originally posted by Mike Smith:
I doubt the varmint guys are shooting 20k rounds a season either. As I said earlier even switching mags can open up your group size. That is why serious high power competitors test a lot of different mags and mark the best ones. There are just a lot of factors in a gas operated system that can affect your group size. Now the difference isn't huge, but an extra one inch spread in your group can be all the difference between winning and loosing especially at the longer ranges. I think you and I are actually on the same page we just are not (or at least I am not) being concise enough. We are basically in agreement but looking at it from 2 different perspectives.

20k is a lot of rounds out of any caliber Mike. Sounds like you don't fancy AR's.

Read this:

http://www.6mmbr.com/gunweek090.html

His last five shot group was .257. That's with an AR15, with a accuracy robbing magazine, semi-auto, and probably the most exotic thing on that rifle is the premium cut rifling barrel. Everything else was basically off the counter run of the mill components. Don't tell me that AR's won't shoot as good or better them many bolt rifles. That's just one rifle of many I've seen shoot that well. Yes I know the bench rest shooters will beat it. There systems and techniques are to the extreme and they have it pretty well perfected, but I'm talking more "normal" bolt action rifles.

No I do you have me all wrong. I just know what that kind of shooting does to the barrel. This is true of any rifle. What I am saying is it is the caliber that will burn the barrel more quickly because of the lack of efficient powder burn in 243. Like I said before each round for a microsecond is a 1200 degree torch because all of the powder does not burn in the cartridge but some in the barrel. It is a cumulative thing. Now 20k rounds will normally only give your throat and muzzle about a 1 on the degree of degradation in the erosion. Maybe even two depending on the load. It is my belief with this caliber that will be sped up. I love Ar's and shoot high power across the course with one. The only problem normally with the 223 vs the 308 is keeping the 223 from going subsonic at about 800 yards or so. That is why 77 grn bullets and hot loads. Again a gas operated system needs a lot more things in tune than a bolt gun. One is not better than the other. It just has a few more things to look after is all. A bolt gun by its design is a KISS principle. Less moving parts and tech less to go wrong. I shoot bench rest too. I have two friends that are world record holders. Andre was number 11 in the world when he stopped competing. Tom still holds the record for 1000 yards I believe. A little over a 1 inch group at 1000 yards and all 5 in the x ring.
I wish I could a group half that good. It is these guys that have taught me a lot. I am always still learning. I am not sure where you got the idea I didn't like the AR platform. I guess I didn't come across right. I apologize for that.

Not problem Mike, we're fine. I agree the bolt rifle should be better as said less moving parts.

Couple summers ago I put together a 6x45 AR 15 with a Lothar Walther stainless bull barrel. Free float tube and match trigger. Just ran the 5.56 brass into the Redding 6x45 sizer die and the first shots with that was single five shot holes with a variety of bullet brands and weight. Ironically the 100 grain round nose Hornady, by no means a match bullet, shot .250 groups right off the bat. I have a 70some grain cast bullet for it and it shoots 1/2 inch or less and at high velocity. Most my other AR's shoot similar.

Yes that guy did shoot a fantastic group with that dang black rifle.

Send it in for a new barrel. Ask for your parts back. Buy an upper vise block and an armorers wrench. 10 minutes to change caliber.

Boy howdy! I've got an AR-10T with a .243 tube on it. Came from the factory with the 26" blue Mike Rock bbl.

I bought it used with @700 rds down the tube. I've put 200 or so down it myself. It is clover leaf cutter with several different weight bullets. It currenly wears a leupold 6.5 x 20 in Leupold rings. I also put a Geiselle HSM in mine.

What are they good for? Poking holes in things to make them die, poking holes in paper to see how close you can get them together, making noise, burning nitrocellulose, making smiles. That's the short list.