barrels

[jets]

anyone know where to get a new barrel for a cetme sporter. im thinking of doing a barrel press and may not want to use the old one depending on triple
frame being welded instead of soldered..........oh yea cai steel receiver so my first task will be finding the barrel pin. hopefully i wont screw that up. great info here on how to do that though.:rockon:

[hulygan]

Gunbroker would be your best bet. also where are you located? someone near you might own a lathe and could help you clean up the weld, and turn it uniformily smooth instead of uneven by hane to remove the weld.

[drine]

Some people were getting PTR barrels, IIRC. You can also check HK parts. They have them and I don't the prices are too extreme. If you have the money, a new barrel is the way to go. A new tripple frame isn't expensive either.

[big jmh]

Bravo 5 also shows to have new barrels

http://store.bravo5.com/servlet/StoreFront

[cenote811]

I know this is probabley a "dumb question", but here it is anyway. I have a CETME Sporter and of course like all CETME's, it has the flutted chamber which assists in letting the gases to discharge when fired. Because the CETME functions on roller bolt blowback basis, is it possible to replace the flutted barrel with a non-fluted barrel that could safely handle the higher pressures, like Winchester 308 at 62,000 psi vs CETME fluted barrel at 52,000 psi and if so would the rifle cycle properley re: blowing back the bolt and what about the head space issue? If so, that might solve the thin case commercial rounds issues and availability of ammo. I don't know enough about it, so thought I would ask.

Thx! cenote11

[Smokehouse69]

I know this is probabley a "dumb question", but here it is anyway. I have a CETME Sporter and of course like all CETME's, it has the flutted chamber which assists in letting the gases to discharge when fired. Because the CETME functions on roller bolt blowback basis, is it possible to replace the flutted barrel with a non-fluted barrel that could safely handle the higher pressures, like Winchester 308 at 62,000 psi vs CETME fluted barrel at 52,000 psi and if so would the rifle cycle properley re: blowing back the bolt and what about the head space issue? If so, that might solve the thin case commercial rounds issues and availability of ammo. I don't know enough about it, so thought I would ask.

Thx! cenote11

Sure you could replace the barrel with a non-fluted barrel, but it would not function. The flutes are the 'gas system' for the Cetme and all delayed roller blowback rifles. The expended gas from the flutes, blows back around the case and forces the case back and partially forces the shell out of the chamber. If you don't have flutes you won't be able to cycle the rifle at least not semi-automatically. Cetmes are designed to use Nato rounds, they will function with commercial and can be shot safely, the only danger is that you might have a case seperation because of the higher pressure and thinner cases of commercial .308.

[86thecat]

IIRC the flutes were introduced to allow the Cetme to function with dry ammunition. There is a story that during development the ammo was coated with olive oil to allow extraction (of the entire case).

These rifles use a roller DELAYED blow back locking system. The problem is that the system can't delay bolt movement until pressure drops enough to allow extraction. Think of the brass case as a balloon which is forced by pressure (burning of propellant) against the sides of the chamber as well as back against the bolt head. If the bolt head moves back further than the brass can stretch while pressure holds the sides of the brass tight against the chamber walls the brass will tear. The flutes help equalize pressure from inside the case with the area between case and chamber so the brass doesn't stick to the chamber walls, allowing the gun to cycle. The flutes run from the case mouth almost all the way back to the case head, the short portion not fluted allows the case to seal the chamber and military brass is strong enough to not tear. As Smokehouse pointed out, no flutes, no workee.....

Hope that helps.

[cenote811]

Smokerhouse and 86 thecat, thanks men. That answers my question. I'll go with what the Spanish Lady gives me. She's a beaut.

cenote811