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PSL 308 conversion?

25K views 61 replies 19 participants last post by  patjsimpson 
#1 ·
Ok I ordered a PSL from Apex. Its the 4th July special. $ 289. I know that its still up there but at some time I think they will be pretty scarce. I cant tell a lie I also posted on the WG. I can get the barrel chambered for 308. The mags for the Psl are a little pricey side. I thought I would investigate the conversion option. What mod does the bolt need [rim verse no rim] and could you use a different mag or is this far fetched. Any input is welcome. Thanks Brad.

P.S. Im still a loyal Gunco member.
 
#30 ·
I was reading that it was unsafe to convert the 54r to .308 because it lacks the third locking lug found on the Saiga .308
were did you read that and what is there proof???????? I have spent the lasst 6 years tring to find any thing in writing from a reputable source that tells what pressures a 2 lug trunion is safe at. an ii have yet to see any one blow up a 308 conversion.

I started the orginal 308 conversion thread here like 5 years ago and there is a ton of info on it. read all of it and then decide.

WILL I TELL YOU THE CONVERSION IS SAFE? NO HAVE I DONE THE CONVERSION ON NUMERIOUS 308 PARENT CASE ROUNDS? YES. DO I LOAD TO THE MAX OR SHOOT FACTORY LOADS / NO.

IF I COULD GO TO THE RUSSIAN AK FACTORY AND ASK TWO QUESTIONS IT WOULD E AT WHAT PRESSURE WILL A STANDARD AKM AN M70 TYPE TRUNION PROOF OUT AT AN

WTF WERE YOU THINKING WITHT HE SITE RADIOUS AN TRIGGERS.

THERE IS BASICALY ZERO INFO OF AKS AND WHT PRESSURES THEY WILL FAIL A PROFF TEST AT. I HAVE READ THAT THE SAIGA IS THREE LUG BECAUSE IT FAILES THE CIP TESTING BUT I HAVE NEVER SEEN AN OFFICAL DOCUMENT. I HAVE THERE ARE OTHER REASONS FOR THE THIRD LUG AN KEEP IN MIND THAT THIRD LUG DONT COST 10 CENTS MORE TO HAVE THERE.

IN ADDITION TO THE 3RD LUFG THE BOLT HEAD IS WIDER AS WELL BUT IF THE SIDES OF A 308 SAIGA BOLT WERE MACHINED SLIGHTLY IT WILL FIT IN A STANDARD TRUNION. I HAVE STARED AT MY 308 BOLT AND STANDARD BOLTS FOR HOURS.
 
#32 ·
were did you read that and what is there proof???????? I have spent the lasst 6 years tring to find any thing in writing from a reputable source that tells what pressures a 2 lug trunion is safe at. an ii have yet to see any one blow up a 308 conversion.

I started the orginal 308 conversion thread here like 5 years ago and there is a ton of info on it. read all of it and then decide.

WILL I TELL YOU THE CONVERSION IS SAFE? NO HAVE I DONE THE CONVERSION ON NUMERIOUS 308 PARENT CASE ROUNDS? YES. DO I LOAD TO THE MAX OR SHOOT FACTORY LOADS / NO.

IF I COULD GO TO THE RUSSIAN AK FACTORY AND ASK TWO QUESTIONS IT WOULD E AT WHAT PRESSURE WILL A STANDARD AKM AN M70 TYPE TRUNION PROOF OUT AT AN

WTF WERE YOU THINKING WITHT HE SITE RADIOUS AN TRIGGERS.

THERE IS BASICALY ZERO INFO OF AKS AND WHT PRESSURES THEY WILL FAIL A PROFF TEST AT. I HAVE READ THAT THE SAIGA IS THREE LUG BECAUSE IT FAILES THE CIP TESTING BUT I HAVE NEVER SEEN AN OFFICAL DOCUMENT. I HAVE THERE ARE OTHER REASONS FOR THE THIRD LUG AN KEEP IN MIND THAT THIRD LUG DONT COST 10 CENTS MORE TO HAVE THERE.

IN ADDITION TO THE 3RD LUFG THE BOLT HEAD IS WIDER AS WELL BUT IF THE SIDES OF A 308 SAIGA BOLT WERE MACHINED SLIGHTLY IT WILL FIT IN A STANDARD TRUNION. I HAVE STARED AT MY 308 BOLT AND STANDARD BOLTS FOR HOURS.
It was in conjunction with that custom heavy barrel PSL. I can't say they had any proof other than higher chamber pressure and the lack of a third lug. I certainly am not qualified to know myself that is why I asked. Please educate me because I would love a .308 PSL.

Thank you
 
#31 ·
The M76 bolt and bolt carrier can be bought for $150. I'm sure there are PSL owners that would buy the spare 7.62x54R bolt
ID GO THAT ROUTE BEFOR WELDING ON A BOLT.

THERE ARE A LOT OF WAYS TO LEGENTEN A BOLT YOU CAN ADD AN EXTENSION TO A SMALL STEM BOLT THAT SLIDES OVER THE EXISTING STEM AND THEN MAKE THE OFD FIT A LSRGE STEM CARRIER THEN WHILE YOU ARE AT IT ADD A SPPRING LOADED FIRING PIN AS IF YOUR GOING TO SHOOT TRUE 308 THEN YOU SHOULD HAVE ONE AN IF YOUR GOING TO HAND LOADF ITS GOOD IDEA AS WELL SO YOU CAN USE STANDARD PRIMERS. SLAM FIRES SUCK ON SOFT PRIMERS. AN YES IT DOES HAPPEN i KNOW FOR A FACT.
 
#33 ·
read the 308 conversion page a lot applies to a psl as it appears the trunion is vry close to a m70 or rpk. there is all kinds of discussion but when its all over there is no real answer as to what is the safe limt of an AK or PSL bolt an trunion.

I can tell you I have loaded 7.62x39 in these guns untill the primers were piercing an the brass was flowing into the extractor port. likley around 65,000 PSI or even more. a 22-250 rounds is at 65,000 psi an it will not pierceprimers or have brass flowing into the extractor groove. so its possable I have hit 70,000 PSI. no way to know but Im sure it was well over 60,000 PSI. there are tons of variable . the 308 galil uses a two lug bolt an it looks identical to a standard x39 bolt except the bolt face is opend up.

untill some ones poneys up the cash an takes a few variants an has them profesional proff tested to a point of distruction w will never know an it wpould have to be dome with multipul guns to prove that there is a average pressure were failure or at least head space begins to change. we will not have any facts on the matter.

I have conversions an i have shot factrory ammo in 243 an 308 but it really proves nothing. i load in the middle of the range.

Imo trusting military surplus ammo that was made 60 years ago by god knows who and how an to what specs is a bad idea .
 
#34 ·
Read this thread from start to finish i started it in 2005 its likely the most involved conversation about the matter inthe world. there are some pretty smart guy in there an ton of info. good discussions on PSI vs CUP SAMMI SPECS VS CIP ETC.

IMO its a must read if your going to do a conversion of any calibur with a bigger bolt face an higher pressures.

http://www.gunco.net/forums/f244/308-ak-18443/
 
#36 ·
haven,t handled one but... what did the israelis use for the bolt in their .308 galil. i would trust them to have tested thoroghly before sending out to troops... just a thought and question
from the pictures Ive seen it looks just like a 7.62x39 bolt but with a bigger bolt face.

I had read stories of the Galil falling ocasionaly but I cant find them any more.

considering the AR 15/m16 has bolts fail all the time id feel safer shooting the Galil .

there are very few documented reports of any ak style bolt failing.

if some one wants to send me a bolt an trunion. Ill load a 308 or 243 build to the max an do some imporvised proof testing.
 
#37 ·
The Galil may use better steel than what they're using in Russia. The Galil was designed before there were mandatory CIP overpressure proof testing required in Europe. The Russians tried to make a two lug 308 AK but they wouldn't pass the 125 percent pressure testing. They went to the three lug bolt. The bolt head and right bolt lug of the Yugoslavian 308 M77 AK and 8 mm M76 are larger than a standard AK bolt. The 308 Valmet bolt is also larger in the same way. In a stamped receiver I would stay with an RPK type trunnion and use a 308 Galil bolt or if using a PSL, use an M76 bolt.
 
#38 ·
The Galil may use better steel than what they're using in Russia. The Galil was designed before there were mandatory CIP overpressure proof testing required in Europe. The Russians tried to make a two lug 308 AK but they wouldn't pass the 125 percent pressure testing. They went to the three lug bolt.
That rumor has been around for a while, there is no data to support and authenticate that rumor.

The bolt head and right bolt lug of the Yugoslavian 308 M77 AK and 8 mm M76 are larger than a standard AK bolt. The 308 Valmet bolt is also larger in the same way. In a stamped receiver I would stay with an RPK type trunnion and use a 308 Galil bolt or if using a PSL, use an M76 bolt.
Incorrect. As I Stated earlier the M76 bolt is has the same lug dimensions as the M70 bolts. In addition the AK74/AK100 bolts have thicker lugs than the AK47,AKM ,PSL, and M76.

If you wanted to use the AK74/AK100 bolt you would have to lengthen the stem, replace the firing pin with one of proper dimensions, open up the bolt face to the proper dimensions, modify the extractor, rework the extractor cut out on the bolt stem, sleeve your PSL bolt carrier for the small stem bolt. The Saiga 7.62x39 bolt would require less material removed from the bolt pocket and the extractor. Kvar has them at the moment.
 
#41 ·
With .308 ammo costing what? five or TEN times as much as 7.62 x 54 ammo, I don't see how a difficult & expensive conversion will make up for the price of a few mags. Keep in mind the PSL mags come & go. Don't be surprised if half way through your build they come back to four in a pouch for $100.00.
Mutt builds are cool no doubt. I have all the parts in a box buried in the kit pile to try a PSL in 30-06 using BAR mags.......someday......if I live that long!..Heh...heh
Either way, good luck!

Brad
 
#43 ·
Excellent side by side comparison Tank. Thanks for posting those.
 
#44 ·
That is a very good side by side. Res. quality is good the zoom is clear. Do you have a AK 47 bolt with extractor that you can post also. I dont have one or I would not ask. Lying down so I can see the bolt face if I might be picky. Thanks Brad
 
#46 ·
I have only posted in regards to the 8mm Mauser M76 bolt dimensions.

That is a very good side by side. Res. quality is good the zoom is clear. Do you have a AK 47 bolt with extractor that you can post also. I dont have one or I would not ask. Lying down so I can see the bolt face if I might be picky. Thanks Brad
Did you mean to say AK74 bolt? If not the M70 bolt is a spitting image for the type 2 and 3 AK47 bolts. The later large stem bolts (AKM, Stamped M70, ect)will have scallop relief cuts in the stem. After that they swapped to the narrow stem bolts for the AK74 and AK100s.

In the pictures the first bolt is a Polish 5.54x39, second is a 7.62x54r PSL, third is 8x57(7.92x57mm) M76, and the last is from a milled M70 in 7.62x39.
 
#48 ·
The two lug 308 bolts aren't known for instantly failing. The Russians had a issue with the then new mandatory CIP 125 percent proof testing. I know somebody that made a 308 AK using a Cold Steel solutions M70 blank, an M70 parts kit and barrel and a 308 Galil bolt. He positioned the trigger guard and magazine back in the receiver similar to a 308 Galil instead of cutting the trunnion for a standard position magazine placement. He reamed the M70 barrel for 308 Winchester. I think he said he to cut the trunnion to clear or feed the cartridges. I'm not sure where this cutting was on the trunnion or if it was to clear the cartridge width or to somehow clear the 308 Galil magazine he used. I don't think I'd try it with an AKM trunnion.
 
#49 ·
The two lug 308 bolts aren't known for instantly failing. The Russians had a issue with the then new mandatory CIP 125 percent proof testing. I know somebody that made a 308 AK using a Cold Steel solutions M70 blank, an M70 parts kit and barrel and a 308 Galil bolt. He positioned the trigger guard and magazine back in the receiver similar to a 308 Galil instead of cutting the trunnion for a standard position magazine placement. He reamed the M70 barrel for 308 Winchester. I think he said he to cut the trunnion to clear or feed the cartridges. I'm not sure where this cutting was on the trunnion or if it was to clear the cartridge width or to somehow clear the 308 Galil magazine he used. I don't think I'd try it with an AKM trunnion.
 
#50 ·
Im still on the fence with my psl build. The pressure from a .308 150gr. is not mutch more than a 7.62x54 so the boldt lug issue is not that bad. What is holding me back is the boldt face dia. and the extractor. I have a .308 and a x54 barrel with some mags for bolth I just need some body to shake the fence. Muttman.
 
#51 ·
Hang in there Mutt Im still waiting on the receiver and barrel. I have been busy with a few other things. I have had some advise from a old timer gunsmith and as soon as everything is in front of me then the process will get more detailed.
 
#52 ·
So, am I deducting that if the M70 bolt tail was extended, it may work for a 8mm build with the psl parts kit, providing of course, that the bolt face be widened for the larger rim of the 8mm or 308? Is that what I read or no? Cause I have both in hand and am going out to look them both over here shortly.
 
#53 ·
No, the 54 case head is larger than the .308 and the 8mm so you would need to install a "ring" for the case head. if you have a 8mm boldt then the locking luges size is the question are they proper size. BTW an 8mm and .308 case head are close in size to work.
Muttman.
 
#54 ·
So, am I deducting that if the M70 bolt tail was extended, it may work for a 8mm build with the psl parts kit, providing of course, that the bolt face be widened for the larger rim of the 8mm or 308? Is that what I read or no? Cause I have both in hand and am going out to look them both over here shortly.
the 8mm is a lot longer than a 7.62x54r but if might be doable . there was a 30-06 Sagia that I have never seen but there are pics on the net so it can be done.

the 8mm is pretty long. im sure the bolt could be extended some how to work on a psk carrier . I considered it at one point myself . opening the bolt is easy . done a bunch .
 
#56 · (Edited)
I think your best bet would have been to start out with a M76 kit as their mags can be used for 8mm, 308, 30-06. I am sure you could use a stamped receiver with an M76 but you would need to get a trunnion or milled stubs that are shaved down.

I myself and doing an M91/M93 clone when I get the chance.

https://en.wikipedia.org/wiki/Zastava_M91#/media/File:Sniper_Zastava_M91.jpg

Kind of reverse of what you are doing.

-Pat
 
#61 ·
I was wanting to do that as well Pat, but just never had the chance. (way too much going on.) If you get time to do it, please document so I can live vicariously through your posts. LOL.
 
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