17 Garin Ar15 project

[william t. oviatt]

ckp

I have had most every caliber based upon the 30 Carbine case, for the game you mention, I would recommend the 6mm Garin. This would be a much better suited caliber to sound moderation and far more versatile bullets selection. Second would be the 22 Garin, I just really liked the 6mm for an all-around caliber in a 16 grain powder capacity cartridge! It is like a modern version of the 25-20 that was King of the small game cartridges for many, many years, before so many other options came along!!!!

just my thoughts

Bill

[22_boomer]

Originally Posted by ckp

G'day Folks,

After lurking here for a while, I decided to join up. Firstly thanks to everyone
for all the great info I have already absorbed. Especially 22 Boomer who I was lucky enough to bump into via another forum.

Now down to business. I am a commercial rabbit shooter in NZ and normally use a suppressed CZ 452 with a Shilen barrel in 17HMR. I want something with a bit more legs, but not as noisy as the suppressed 223 that I also use. I have looked at just about every option and ended up at 17 garin. 17vha was first choice but 4.6x30 brass is impossible to get here. I also need a semi auto. So 17 Garin ar15 it is.

The plan is a 20inch Lilja 1 in 9 barrel with pistol length gas system and adjustable gas block. As it will be a high volume gun, we are going to tig weld and remachine the bolt face to accept the 17 Garin properly. Locking lugs to be thinned out as required to clear the mag lips. Mags will be 15 rnd or maybe 30s M1 or 30 carbine mags tig welded into a modded steel 5 shot AR15 mag.

I know a few guys here have built similar guns so I would appreciate any feedback or advise on the above plan. Also would a low mass bolt carrier like the JP enterprises one help with cycling in this low energy situation.

Sorry about the wall of text. And thanks in advance.

ckp,
I have rounds that are smaller in diameter (17 VHA) than the standard .223/5.56 rim size and installed a ring filler and brazed in place and then did mods to allow the ejector to function in the smaller diameter bolt face and also did some mods to the extractor to allow it to close in further to fit the cartridge correctly. Problem I see is the M1 Carbine cartridge rim is only a bit smaller than the .223/5.56 and can actually function with the existing bolt face although a sloppy fit. Your Idea to tig the bolt face is beyond my capabilities but a good machine shop should be able to make it true. I use M1 Carbine Mags with my 22 TCM using long bullets like 40gr V-max and I did not need to do any mods to the locking lugs on the AR bolt. The existing bolt lugs fit through the magazine feed lips for me just fine. I'm not sure but I may have sent you a URL for a fellow that has made a magwell adapter for the M1 Carbine mag with the necessary feed ramp so all you do is slap in the loaded mag, operate the charging handle and let those rabbits know who's boss. Just in case you want it, here is the URL: http://thearguy.com/ -- he also has a web site: http://762x25tokarev.proboards.com/
The fellow's name is Tim and this is a second business so he may not get right back to you. Also, he builds AR's that shoot the M1 Carbine round but they are test rifles right now but he may be able to do that bolt mod for you. I asked Tim at one time and he said he was going to correct that bolt fit problem also. Tim does not show the M1 carbine magazine adapter on his site so it would be best for you to contact him.

Edit to add: I contacted the fellow Tim and he does not want to bother with the AR bolt. I checked myself and it's a very close fit so you could start with a standard bolt but you may need to open the Extractor a bit since the M1 carbine cartridge case has a pretty thick rim. Your Idea about the magazine may be good also -- a lot less expensive.

[TOU]

Originally Posted by 22_boomer

ckp,
I have rounds that are smaller in diameter (17 VHA) than the standard .223/5.56 rim size and installed a ring filler and brazed in place and then did mods to allow the ejector to function in the smaller diameter bolt face and also did some mods to the extractor to allow it to close in further to fit the cartridge correctly. Problem I see is the M1 Carbine cartridge rim is only a bit smaller than the .223/5.56 and can actually function with the existing bolt face although a sloppy fit. Your Idea to tig the bolt face is beyond my capabilities but a good machine shop should be able to make it true. I use M1 Carbine Mags with my 22 TCM using long bullets like 40gr V-max and I did not need to do any mods to the locking lugs on the AR bolt. The existing bolt lugs fit through the magazine feed lips for me just fine. I'm not sure but I may have sent you a URL for a fellow that has made a magwell adapter for the M1 Carbine mag with the necessary feed ramp so all you do is slap in the loaded mag, operate the charging handle and let those rabbits know who's boss. Just in case you want it, here is the URL: http://thearguy.com/ -- he also has a web site: http://762x25tokarev.proboards.com/
The fellow's name is Tim and this is a second business so he may not get right back to you. Also, he builds AR's that shoot the M1 Carbine round but they are test rifles right now but he may be able to do that bolt mod for you. I asked Tim at one time and he said he was going to correct that bolt fit problem also. Tim does not show the M1 carbine magazine adapter on his site so it would be best for you to contact him.

Edit to add: I contacted the fellow Tim and he does not want to bother with the AR bolt. I checked myself and it's a very close fit so you could start with a standard bolt but you may need to open the Extractor a bit since the M1 carbine cartridge case has a pretty thick rim. Your Idea about the magazine may be good also -- a lot less expensive.

Hey Boomer,

Great information, thank you for posting it. I could have swore I read a thread somewhere about your 22-TCM AR build. Would you mind posting it or PM'ing me the information please?

Thx,

TOU

[22_boomer]

TOU,
The 22 TCM is very simple and the only problems are getting the barrel you want made and the type of magazine setup you want. I'm using the pistol length gas system since it's the shortest factory parts gas system you can have and it seems to work fine with my hand loads. The magazine setup is another story. I use a 7.62X25 Tokarev AR adapter and the PPS-43 magazine shortened for 10 rounds for light bullets like the Burger 30gr and Hornady 35gr V-max. A loaded cartridge longer than 1.36" would require a longer magazine and one fellow actually uses a standard AR mag but of course the more rounds in the mag the more they get screwed up and won't feed. I use an M1 carbine magazine and a home-made adapter for the longer rounds but there is a possibility that Magpul mags can be modified to allow for shorter rounds and I have done this for other cartridges. I have not tried the modified Magpul with the 22 TCM but it should work although I can't say how many rounds it will hold without cartridges getting misaligned. My barrel is a 16" standard carbine weight with a 1:12 twist and I actually prefer to shoot the lighter bullets. There are some things to remember -- the factory ammo has a big soft nose and may get deformed in the feeding process. It is best to use a carbine setup or at least a buffer with the weight of a carbine buffer and a plus for helping mild loads work is a lightened carrier although a standard AR-15 carrier will work but try to stay away from the heavier M-16 carrier. This is an inexpensive lightened carrier but it's out of stock right now -- https://www.righttobear.com/RTB-AR15...bn16-lw-co.htm
There are no mods necessary to the bolt but other add-on's like adjustable gas block are totally your decision. If you have a problem finding a 22 TCM AR barrel or the 7.62X25 Tok magazine adapter you can try looking here: http://thearguy.com/products-page/di...erated-barrels
the fellow also makes a heavy 22 TCM barrel although I have no idea where he gets the blanks.

Edit to add picture: This will give you an idea as to how small the 22 TCM carbine is with a 16" barrel. Muzzle velocity is 3000fps and may be higher if you really want to push it. You can almost aim it once, close your eyes and all the bullets will shoot to where you want them.

[22_boomer]

TOU,
Forget the use of modified Magpul mags. I just checked the shortest setup I have for rimless 256 Winchester Magnum and the follower is still too long. If you don't want to make your own magazine adapters then contact Tim at this URL: http://thearguy.com/faq

If the price of the AR guy's adapter is too high then you can try http://cncgunsparts.com/ar-15_m-16_762x25_uppers
I don't know the cost of the cncguns adapter but I believe it is less and it's a drop-in adapter made of steel. It's about 1/3 of the way down the page.

[ckp]

22 boomer,

I tried a few times with no luck to get a hold of the arguy. will keep trying. I did
see a picture though and it looks like the actual m1 mag will sit about 3/8 of an inch back from the front of the ar15 magwell. I wonder if this may create issues with 17 garin as potentially the case is almost out of the feed lips before the shoulder is up into the barrel extension. I may also be over thinking it. How far forward did you have your m1 mag in the ar magwell for your 17 projects, as it sounds like you had good luck with yours. Also good news about the locking lugs fitting through the mag, hopefully one less thing to be machines= less $$$$

[22_boomer]

Originally Posted by ckp

22 boomer,

I tried a few times with no luck to get a hold of the arguy. will keep trying. I did
see a picture though and it looks like the actual m1 mag will sit about 3/8 of an inch back from the front of the ar15 magwell. I wonder if this may create issues with 17 garin as potentially the case is almost out of the feed lips before the shoulder is up into the barrel extension. I may also be over thinking it. How far forward did you have your m1 mag in the ar magwell for your 17 projects, as it sounds like you had good luck with yours. Also good news about the locking lugs fitting through the mag, hopefully one less thing to be machines= less $$$$

I need to show a picture of my magazine setup so you can get an idea of how far back the M1 mag sits. The M1 mag can't be too close to the little feed ramps on the barrel extension because as the round is being pushed to the chamber it is still slightly restricted by the feed lips of the magazine. My magwell adapter and magazine were made as one piece but you can either make the adapter as a separate piece that you can drop into the magwell from the top or make the magazine and magwell adapter one piece that slides in as a big magazine -- not really that big -- or buy one of Tim's adapters. I believe he can also sell modified M1 mags with the mag-catch notch cut in them but again I don't know the price.

below is a poor picture of my M1 mag with the attached adapter -- note that the spacer at the front is actually a ramp to help guide the round.

The magazine and attached adapter are the full size of the AR Magwell with the M1 Magazine set all the way to the rear.

By the way, the reason the fellow doesn't want to bother with modifying the pocket in the bolt face is because it is so close to correct that he said it is really not necessary to modify. I would build the rifle and use a standard AR bolt and test the heck out of it and if you feel the bolt face needs work then go and do it -- but try the standard bolt first -- less work for you.