www.MG42.us

Tumbling ammo with imr powder is a no no, it breaks the sticks and rubs off the coating changing the burn rate.

That would be the first I've heard of that. I can tell you none of the stuff we had collected was tumbled by the end user. Just opened up the plastic bags and inserted ammo. OFV 75, 77 and 79 I know for sure were bad.

Majority of Indian ammo I have is 98,99, and 02. Someone had [before I bought it] told me that the later production stuff was OK, thats why I bought so much. I have run some through my 1919 with out a hitch. Could the problem ammo have been in the earlier years? Any comments on the newer stuff like 96 to 02 production?

While I have no personal experience with those years let me ask you this. If they are dumping 1970's ammo that has problems...why whould they be dumping 1990s and 2002 ammo also? I mean in terms of military ammunition, thats pretty new stuff. Most surplus ammo you see on the market is 20+ years old, not less then 5. After seeing what this stuff is capable of doing to a firearm, I stay away from all of it.

Hank, do you feel that the round was not fully chambered when you pulled the trigger? Not knowing the workings of your convertion, but will the FP hit the primer when the gun is out of battery? The FP should not be able to protrude through the bolt face unless the rollers are in full lock-up and the rear bolt has moved full forward about 1/4 ". You may have a FP that is too long???
The other item to address is the chamber. Make sure it is bright, and clean. My 42 will not fire unless the bolt is in FULL lock-up. If it doesn't by a slight amount, the round will not cap. Polish all parts and chamber.
Glad that you were not HURT. As far as a mig welder, Weaver in Boise welds his FAs with mig and has never had a problem.
LOL
Weasel

I had similar episode when I had a case neck seperation and the following round stopped prior to being totally chambered. My mig welds held fine though - . It will certainly scare the (Try a different word.) out of you.

The other area watch for is if your hammer follows the bolt. Either because forgot to weld a blocking bar in for the fal trigger, OR

If your trigger or hammer holes are oversized (remember theyre metric) or your pins are under sized. Depending on the degree of wear on your fal trigger parts the sear/hammer engagement can be Damn little and just a bit of slope can result in the sear not engaging the hammer securely. This will lead to doubles, triples and out battery explosions. If you made your pins from scratch, MAKE VERY SURE THEY ARE PROPERLY dimensioned - IIRC theyre supposed to be 4.5 and 5mm. DO NOT USE STANDARD DIMENSIONED DRILL ROD FOR YOUR PINS, unless you start big and turn them down to the right size. ALSO USED METRIC BITS FOR YOUR TRIGGER AND HAMMER PIN HOLES.

I remember chambering a round and pulling the trigger and BOOM. Charging handle was forward. Really couldn't say if something jamed the firing pin like a piece from a punctured primer, or another piece got into the roller preventing full battery. There was a piece of metal between case and chamber which really could have caused the blow up. I just remember pulling the trigger and the surprise boom and the barrel gate blown open. I have found the firing pin was still too long. I had been whittleing away at it after each test session and have gone another .015 shorter.

Sometimes you have to mess with both shortening the Stock FP (I think I removed about 1/8 inch from the rear of mine) AND/OR the spring youre using to hold the FP extension rearward. I found the A. springs weaken over time and B. it seems critical that the spring only allow the extension to protrude 1/8 inch into the wedge at most in its relaxed state. changing spring tension was less critical than this 'magic' protrusion length, in my gun.

Yeah 'hg', these guys are right on,and i would like to add, that I found the 'India'n'308 ammo to have different thicknesses of the rim at the base of the casing. Some fine, but some outrageously thick. This may have caused the non-extraction problem......
Secondly, I must ask, 'is the firing pin in the bolt a "free-flowing' firing pin ??...In-otherwords, the pin moves inside the bolt, without being restrained by a little spring, untill walopped by the hammer from the trigger-group below ???..
I ask this firing pin question, because in the MP-43, the firing pin is this freeflowing' way, and on occasion I have had it go off, by just letting the bolt go foward and chambering a round, thereupon, the firing pin sorta bangs into the primer when the round is about seated in the chamber, because there is no mechanism inside the bolt to keep the firing pin still when chambering a round. :o
Virtually every primer has a slight mark on it after being chambered, if I don't fire the round and withdraw it.
So, is the firing pin 'freeflowing' or restrained until hit by the hammer ? :mad: (did I make sense )

In Pirates bolt set up the original firing pin is used, free floating against a spring loaded driving rod actuated by the hammer strike. So yes, the 2 inch long pin is free floating. I have an idea to plunge cut the bolt head slightly with the appropriate carbide mill bit so I can put a ball point pin size spring on the head of the firing pin.

Hey ya'll I have been able to recoup some of the pictures we had on our Indian Ammo warning thread....to include a blown MG42 with the OFV brass still in the chamber.

http://www.cetmerifles.com/forum/vb/sho ... hp?t=11183

Can you tell me any of the years stamped on the cases that caused these problems ?

1970's and 1990's. We had 75, 77, and 79 for sure go bad. I don't remember what the 1990's dates were.

My dates are, 86, 91, 92, 96, 98, 02. pulled bullets on several rounds of each, nice string powder and no small flakes what so ever, burned each one and burn rate is definately controlled. Looks and burns like IMR4831 [burnt some of that too ]

drooling idiot wrote:everyone else has pointed out the questionable ammo so I'll go a different route.

when you loaded the belt into the MG3 drum you wound it into a nicely rolled up ball right?

wrong the belt should be loosely lapped back and forth inside the drum so the feed mechanism does not have to move the entire weight of the loaded belt to feed the next round. now did this extra weight and increased drag slow your bolt enough to prevent it from ejecting the fired cases or stripping and chambering the BOOM rd. ...... i don't know that for a fact but i am suspicious, so i offer it as a possible suggestion .

I have been wondering whether the belt should be coiled or lapped in those drums. Now I know...

I did have it coiled up not just layed from bottom to top. As I originally said , I had just run a loose whole belt of the same ammo [86 OFV ] withought a problem then put the drum on with belt coiled up unside,then had feed problems.

gunslingerdoc wrote:........... DO NOT USE STANDARD DIMENSIONED DRILL ROD FOR YOUR PINS, unless you start big and turn them down to the right size. ALSO USED METRIC BITS FOR YOUR TRIGGER AND HAMMER PIN HOLES.

What drillrod is pirate using for these conversions on the Fal grip ???

Really couldn't tell you, but I'm going to find out tomorrow and report back.

Hammer pin is fine but I found something else. When I was checking things out mor closely, I striped the receiver except for barrel and barrel bushing, including removing booster. With the barrel gate closed,reached my finger in the slot on top for the feed tray so I could touch the barrel and pushed back on the barrel bushing. Well the damn thing would hardly move, it took a lot of effort. Pulled out barrel and bushing, cleaned thouroughly and reassembled. No better. disassebmbled again and started looking things over more closely. What I found was the front Threaded booster piece had been welded on slightly off center , so when the barrel was in the bushing it was in a slight bind when moving rearward and forward. A person cannot feel this when recouperator is in place because the springs are too strong and you have the leverage of the cocking handle. Honestly I thought every thing was OK with the barrel and bushing until now. I went to my lathe and turned down the end of a 2ft steel bar down so it was a snug fit into front of receiver where booster goes, laid the receiver in the big vise on a folded rag and proceeded to massage it [the steel bar ] with my dead blow. It took about 4 times of a few wacks then checking ease of movement before the barrel really freed up. Now it slides as if it were on bearings. So for those of you who are building or have built your own 42's, this is something not to be overlooked. Just because you put the receiver together and it works [ seems to cycle freely] you may still have a problem in this area. I was experiencing short cycles,sluggish feeding but not all of the time. Just because you can put in the bushing and barrel and the gate closes doesn't mean it's free. So listen up and be sure to make this simple check, it could save a lot of head scratching and cussing. Building this 42 has been 10 times the problems I ever had building my MA DEUCE and 1919's. I have another cure for you-all in another post. I don't type well and I'm out of chicken feed to throw at the key board so I quit for now

Thats why i built this jig...it makes it allmost impossible to reweld it crooked