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Ssarge
September 24, 2008, 17:05
I picked up a minty one at the funshow last weekend for $750 OTD. I have replaced the stock with a USGI mint fiberglass stock, the trigger group with a TRW USGI and the rear sight assy with a USGI set.
I got a mint USGI M14 F/S from Southern Raider and was going to replace the solid f/s on the poly. Then the fun began! There was no set screw to hold the castle nut in place, the castle nut moves about 4 turns. Then the whole shebang is frozen. It looks like it's welded on, so it's Dremel time!
Anyone else have problems with the Poly F/S?

AliYahu
September 24, 2008, 17:17
You got a deal!
The caste nut on mine (recently sold) had a very small allen-head screw holding it on. If it's gone there should be no issue. You are using the correct pliers right?
If you don't destroy the old FH you can sell it to a californian.

Eli

Bentley8
September 24, 2008, 17:33
Don't Dremel yet!

I picked up one a year or so ago and it had the welded fake flash hider. A couple of whacks with a nylon-tip hammer and it broke the welds. Unscrewed the castle nut and whacked a little more. Repeat until you walk the flash hider off.

Some of the welds on these are very weak, like mine. Some are very strong, but it's a good idea to try the hammer first.

Ssarge
September 24, 2008, 19:02
Oh I tried a brass hammer, a rubber mallet and finally a BFH. All to no avail. I had to cut the f/s in 2 places to get it to slide off.
I wanted to keep it intact to sell, but not a happening deal.
BTW-I have a set of real USGI castle nut pliers, I have dealt with the cheap ones before and never again!

Bentley8
September 24, 2008, 19:12
Ssarge, where did you get the USGI castle nut pliers?

Ssarge
September 24, 2008, 19:38
I got them years ago off gunbroker. Got a USGI F/S in the tube, niw M6 bayo and M8 sheath and new in the wrap castle nut pliers for $95.

Ssarge
September 24, 2008, 19:57
Well I got a gas seal, but the f/s won't seat nearly as far as they do on an M1A. Looks like the outer dia of the barrel is larger than an M1As is.
Anyone else experience this?
(and no the splines are not buggered)

Bentley8
September 24, 2008, 21:29
Strange. Can you post a picture?

hockeysew
September 24, 2008, 22:51
Originally posted by Ssarge
Well I got a gas seal, but the f/s won't seat nearly as far as they do on an M1A. Looks like the outer dia of the barrel is larger than an M1As is.
Anyone else experience this?
(and no the splines are not buggered)

Metric threads on the barrel more than likely.

Ssarge
September 25, 2008, 07:14
Originally posted by hockeysew


Metric threads on the barrel more than likely.

Though tight, the castle nut is engaging the threads which are metric.
I have a commercial f/s that should be here today or tomorrow and I'll try it.

vmtz
September 25, 2008, 07:19
If I remember correctly, the threads are different. You need to use a Chinese nut.

Fr. Vince

Ssarge
September 25, 2008, 07:25
The threads are different, but the GI castle nut will often work. It's working in this case. The end of the barrel is a bit larger in outer diameter than the rest/it appears not to have been turned down as much so the grooves could be machined in.

Ssarge
September 25, 2008, 07:54
This guys is seated exactly like mine. About the middle photo.
http://gunbroker.com/Auction/ViewItem.asp?Item=110699093

gunshack
September 25, 2008, 09:40
I finished up my Poly last month, it shoots like gangbusters! USGI bolt conversion, new rear sights, commercial muzzle device, USGI hammer and trigger/sear assembly, and fresh park on the receiver. I want to refinish a few more of the parts and take some photos before I write up a report, but just haven't had time. I'll get to that.

My commercial muzzle device doesn't seat as far on the Poly barrel as it does on USGI or Criterion barrels. I don't think that's uncommon. The original foux flash hider was soldered onto the barrel, I got loosened up with a mapp gas torch.

Ssarge, Keep an eye on your connecter lock. The Chinese connector locks are shorter than GI, they do not protrude from the receiver they way USGI ones do. Some folks have trouble with them walking out and releasing the op rod spring guide when in a USGI stock, which could cause a hellacious jam. You might be able to replace the connector lock with a USGI one, but some receivers are too tight for that. Another safeguard is to glue a piece of a popsicle stick into the stock to block the connector lock from walking out.

BTW: The USGI spec for the muzzle thread is 32 threads per inch (0.0313" pitch) and the Chinese used 0.75mm pitch (0.0295".) The diffence is enough to make the fit of a USGI castle nut to a Chinese barrel hit or miss. Sometimes it works, sometimes it don't.

Ssarge
September 25, 2008, 13:41
Thanks gunshack. I'm going to send mine to Warbird for the bolt conversion and a re-park. I'll likely get him to do the connector lock, my buggered hand makes doing fine work problematic.

Ssarge
September 25, 2008, 17:41
Well after lot's or wrestling and rubber mallet whacks I took the USGI F/S off and put the el cheapo from CTD. It of course fit like a glove and went on without a problem...
Go figure? :cry:

Bentley8
September 25, 2008, 20:45
The one from CTD probably came from China. :wink:

Blackmore
September 26, 2008, 06:12
Originally posted by Bentley8
The one from CTD probably came from China. :wink:

CTD = China Trade Deal?

1MOR
September 30, 2008, 19:57
I passed on a Polytech that a pawn shop had a few years ago. That of course, was before I knew what a few USGI parts and a real stock could do for the weapon. He wanted $600 and I thought that was a bit much. Kick Kick Kick!!! Now hoping to stumble over another, would love to have a build done on a forged chink receiver.

Ssarge
September 30, 2008, 20:45
George they are out there. You just have to look and one will show up.
I screwed up and traded a heel stamped Poly that I got for $650 for an all TRW barreled M1A receiver/bolt. Seemed like a good deal at the time, but I sure wish I had the heel stamped, it was nice.

snowhawk jockey
October 01, 2008, 11:26
Originally posted by gunshack

...Ssarge, Keep an eye on your connecter lock. The Chinese connector locks are shorter than GI, they do not protrude from the receiver they way USGI ones do. Some folks have trouble with them walking out and releasing the op rod spring guide when in a USGI stock, which could cause a hellacious jam. You might be able to replace the connector lock with a USGI one, but some receivers are too tight for that. Another safeguard is to glue a piece of a popsicle stick into the stock to block the connector lock from walking out.


Good deal on the Poly, Ssarge! Mine sure works good. I have the same exposed threads at the F/S after I put the vented and lugged replacement on.

My connector lock opened yesterday. I didn't notice as I removed the mag, then had a fumble match going trying to get one back in. I finally looked in the magwell and saw the spring guide sticking out. GRRR I almost peened the receiver to hold it tighter right then and there, still might. I'll look into the popsicle stick idea first. Gotta pic of your 'stick-in-the-stock, gunshack?

gunshack
October 01, 2008, 12:49
Sorry, I don't. Just cut a piece about 1/2" long and by eye ball glue it into the stock where it will block the connector lock from walking out. Use just a tiny bit of elmers paper glue. It will hold fine, but you'll be able to get it out if needed.

I used my original Chinky stock for my poly build, but I still might put the rifle in a birch USGI at some point. When I do, I'll most likely ream out the receiver to fit a USGI connector lock.

Don't peen it, or you'll have a bitch of time getting it back out when you want to take the op-rod out for cleaning.

cabinetman
October 02, 2008, 13:11
Be sure to check your headspace. Mine was so far out of whack when I got it that the primers were all but popping out. While the receivers are the best out there the bolts are soft. A TRW bolt and new barrel (Barnett air-gauged medium weight) took care of that. I also had a NM flash hider installed. It's reamed out a bit to provide a bit more clearence for the bullet to travel through.

Fred's Stocks offers excellent grade Walnut military M14 stocks, btw. Some I've seen look unissued and fit like gloves. Finally, to fill in the inletted area for the switch, you can purchase a demilled one from Sparrowhawk for cheap and install it. While I don't condone "bling" on my rifles, it does fill the space nicely and appropriately and eliminates having to fill it in with wood.

Rome

Bentley8
October 02, 2008, 13:17
Just a warning, if you do order from Fred's, it can take a long time to ship. My last order took 9 months for two stocks and some handguards (ordered in October 2007, received in July 2008). Some people have waited longer.

cabinetman
October 02, 2008, 13:46
Yeah, I read about that recently. Don't know what's up with that. He's still advertising heavily in SGN, too. Mine did take 3 weeks to arrive but that was a while ago.

Rome