Originally Posted by 1biggun
Originally Posted by 1biggun
Yeah I have to agree with the magazines - those Madsen mags are the way to go. It looks like you'll have to braze or weld some lugs onto the magazine anyway, so why not do it with the cheap ones - $5 apiece from ima-usa.com looks like a winner to me!
Rhino_66 that was the .50 cal round I was thinking of on meppers gun thanks for finding that site. http://www.hodgdon.com/data/rifle/857mmmau.php is a good site for 8mm loads some are pretty light. I want to do the 8mm in a pistol for hunting with a real heavy bullet. I want good knock down power out to 200 yards a 200 grain would be good. I have a friend who has a modern 8mm mauser comercial built and and his safe hot loads do very well against my30-06 I like the madsen mag Idea I am going to order one on monday. wonder how wide they are. the price is right. going to look for material for my milled Yugo kit monday for the 308 conversion
HA! While looking for something else entirely......7X57 BAR mags....$5.00 a pop!
Go here look for MAGAZINE, BAR MODEL D 7mm
Originally Posted by cammobunker
Cool! Man I can't wait to go to Knob creek again this spring. There are so many tables full of bins with all kind of gun parts from the past 100 years. I got so many ideas and things I am looking for now.
Seems like the biggest problem to me is the bolt and trunnion. I need a meaty enough bolt for the round, that's long enough for the round and a trunnion to match the bolt. The rest is do-able. Blank for a reciever. Mags can be modified/welded/whatever to work. But the bolt is the part that has me scratching my head... I don't think a 7.62x39 bolt is meaty enough, and I know it's not long enough. To bad a body can't just order spare parts from the zastava factory.Quote:
Originally Posted by hcpookie
It would be nice to determine CUP pressure, and if it is close to a .308 or a 7.62x39, then I would say the bolt has enough meat out of the box. Would definitely be something I would consider building from a heavy RPK-style receiver just for that extra bit of security. Of course, the "hang time" on a semi is pretty low, so I think the pressure would bleed off fast enough that you would be OK.
Judging from the M76 pics, I am confident that it would work, would just need to get that CUP pressure info before you begin.
Im using a yugo m70 bolt on my 308 conversion. if its heavy enough for that it should handel a a 8mm with a lower cup pressure. some were on this site I read that the M76 ( 8mm mauser) was a 2 lug bolt and trunion set up. bolt length is a issue with the 8mm round I was thinking of extending the bolt and pin out some how. as far as grinding the trunion it would only need to be widend slightly to get a mag to fit it if at all with a m14 mag see sangs posts on the 308 conversion forum. moving the trigger guard and latch is almost a given. I am planing to move the latch piviot back aprox a 1/4" and rework the spring (well the whole guard) and take another 1/4" out of the guard its self this will leave pleanty of finger clearance. ( this on the 308 conv) Bolt face and extracter will need to be opened up as well. the 8mm round is only 6mm longer than the 308 if one were to take say 2mm out of the trunion and 4 more out of the trigger guard mag latch area it the rest would be the same as a 308 conversion. I make my own recivers so moving the trigger group back or the trunion forward is a option as well. If a longer bolt was avaliable I would just make a 3/4" longer reciver moving the front trunion forward. (I made my jig extra long already HEE HEE) as far as gas block and gas port hole size I would go with a L1A1 adjustable gas block and tune it to work with what ever ammo you find cheap. I would not use a Sagia 308 as a starting point when a Yugo kit is only $100 dollars and you are going to not use the barrel. why wreck a 308 Saiga when the whole gun can be built for less than what the Saiga cost to start with? Yugo kit aprox $100 8mm mauser barrel on ebay $15 or less US parts$60 Mags $2.00-$25 reciever blank $15depending what you go with say aprox $250 for all. having a 8mm or other custom calibur you built yourself priceless
7x57 Mauser: 46,000 CUP
.303 British: 45,000 CUP
8x57 Mauser: 37,000 CUP (SAAMI, artificially limited for commercial liability)
8x57 Mauser: 50,000 CUP (As loaded in Europe, commercial and military)
150 Grain Speer Soft Point:
CASE Winchester Primers: Winchester LR
4831 47.0 2325 fps 36,800 CUP
4350 43.0 2315 fps 36,800 CUP
4320 36.0 2270 fps 36,900 CUP
4064 36.0 2305 fps 37,000 CUP
4895 36.0 2310 fps 37,000 CUP
3031 34.5 2335 fps 37,000 CUP
4198 28.5 2225 fps 37,000 CUP
7.62x51 = +/- 52,000 CUP.
Moral of the story - "Military" loads are around 50,000 cup. Both should be doable in a .308 Saiga style build (thicker receiver). The bolt head concerns me too. I think you would be OK, but that extra metal on a Saiga .308 conversion would make me feel much better when I put that up to my face when shooting...
Originally Posted by hcpookie
...see, that's what I was thinking.. peace of mind. The bolt on a standard M70 might not fly apart today.. .might not fly apart tomorrow... but it seems to me they designed it beefier on the larger caliber versions for a reason. M70 trunnion.. no problem with. It's all about the bolt.
As far as a lot of money put into a conversion vs scratch build.. I don't think I'd be saving money starting out from scratch with a dark-bore M70 kit. I'm thinking by the time I get done screwing around trying to lengthen a bolt.. make this work, make that work.. it will have just been easier to rebarrel a .30-06 or .308 Saiga in 8mm and work out a mag that will feed... half the engineering is already done for me. Now... if I could lay my hands on a bolt, carrier and trunnion for an 8mm, .30-06 or etc... then I'd say sure, sign me up for a dark bore kit.
Anyway... still just working it out on paper before I commit to actually working on this... all this information is really helpfull btw. I've went ahead and ordered some mags from IMA to see how they look as a sign of my being comitted to finding a solution.