More Dumb MG42 7.62 Headspace Questions

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Waffentag
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More Dumb MG42 7.62 Headspace Questions

Post by Waffentag »

Well, I spent some time over the weekend reading the Two Volume MG42 book and the previously posted headspace instructions and I have more dumb questions.

Armed with my new Forster 7.62 Go No Go gave, I tested my 4 barrels with my 5 bolts.
Then, I read that one should remove the extractor prior to testing headspace. I tested one bolt head one bolt head on all 4 barrels with and without the extractor and got the same results. So, I did not remove the extractor for the rest of my test?

DQ1. Do I need to go back remove all the extractors and retest for headspace?

When I did try to remove and extractor, I discovered that my Yugo extractor tool would not fit over my firing pin holder/striker. No problem, I swapped MG3 firing pin holder for a Yugo firing pin holder. I also discovered that the only part on my MG3 extractor replacement kit that worked was the extractor. The plunger and spring do not fit. So, I did some more reading. It seems that you have a 90% chance of having good bolt headspace match with a Yugo Bolt on a Yugo or German WW2 8mm Barrel. Your odds go down significantly using a BW MG3 7.62 Barrel.

DQ2/3. Where can one find a BW MG3 bolt Head? Will it improve the odds for a good headspace match?

DQ4. Does changing the firing pin holder/striker have any impact on headspace? (I got a bunch of BW MG 3 spare firing pin holders, firing pins, etc. cheap and have been using them on the Yugo bolts)
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Re: More Dumb MG42 7.62 Headspace Questions

Post by Waffentag »

PS, John, I have all of your translated books on the MG42 and MG3. Yes, I read those also:) I also have some versions that you have not yet translated. You are welcome to borrow them, just want them back.

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Re: More Dumb MG42 7.62 Headspace Questions

Post by JBaum »

I'm always looking for new manuals. I've seen a few that contained the information that is already in other manuals I've translated, so I won't do those because there's nothing new. If there's something new, I'd be happy to have more information.

Manuals can be scanned (400 DPI or higher is preferred) and emailed to me at John@Germanmanuals.com

Or they can be mailed to me. I'll return them within a day or two after I scan them. I've done that with manuals from Belgium, England, Texas, and Oklahoma, just to name the ones I can quickly remember.

Thanks.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by hakentt »

Armed with my new Forster 7.62 Go No Go gave, I tested my 4 barrels with my 5 bolts.
no wonder why I can't find any 7.62 barrels. People are buying up to 4 barrels for their MG. So what are the results of your test?
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Re: More Dumb MG42 7.62 Headspace Questions

Post by Waffentag »

"no wonder why I can't find any 7.62 barrels. People are buying up to 4 barrels for their MG. So what are the results of your test?"

Well, to answer your test result question.
I used white paint and labeled my 7.62 Number 1-4. On the Bolts, I just used the numbers already on them. The test using one bolt head with and without the extractor got the same headspace results. No bolt lock up on the No Go Gage for all four barrels. Barrels number 1 and 2 would not lock up with the go gage. Barrels number 3 and 4 were a go with the go gage.

Testing with the other five bolts (with extractors in), None of the four barrels would close on the No Go Gage with any bolt. I found one bolt head that would not close with the go gage with any barrels. I found one barrel that I could get none of the bolt heads to close on with the go gage. One barrel worked only with one bolt. Two barrels headspaced good with three of the bolts.

I think that I need a couple of MG3 bolt heads for two of the barrels

At one time, I had five 7.62 barrels and three 8mm barrels, then I traded one 7.62 barrel for a Yugo 8mm Barrel since I did not want to shoot my minty German WW2 Barrels. Then I picked up a second Yugo parts kit with an 8mm barrel. You just can not have enough barrels.

Anyone have any answers to my Dumb Questions above.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by JBaum »

I have more time tonight:

DQ1 The extractor should not protrude past the bolt face, therefore it will not affect headspace, which is determined by the rollers in the barrel extension grooves, and how far the barrel is screwed into the barrel extension (how far it protrudes into the inside of the extension).

DQ2 MG34.com had a bunch of MG3 bolts. They're website is down for inventory, but they will be at Knob Creek. The have the tables around my spot there, and I've already talked to the owner who will be there Friday and Saturday only. Wait till his website comes back online and check.

DQ3 Headspace is determined by two dimension (see DQ1), so if one is really off, mating it with any bolt head that is within specs won't help, unless it's really off in the opposite direction.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by Waffentag »

Thanks John, I emailed him, He has none?

Thanks Pat
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Re: More Dumb MG42 7.62 Headspace Questions

Post by JBaum »

Waffentag wrote:Thanks John, I emailed him, He has none?

Thanks Pat
Pat

"He has none?" What does that question mean? You emailed him when he says he was closed for inventory? I'd probably tell you I didn't have anything either if you asked when the website says I'm closed for inventory.

What did you ask for? If you asked for bolt heads, I'm sure he doesn't have any for sale. Nobody would. That would leave them with a bunch of bolt housings that nobody wants.

If you asked for MG3 bolts, he should have some, but he's closed for inventory, so he doesn't have any for sale. See the last sentence in the DQ2 paragraph above.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by hakentt »

Waffentag wrote: Well, to answer your test result question.
The test using one bolt head with and without the extractor got the same headspace results. No bolt lock up on the No Go Gage for all four barrels. Barrels number 1 and 2 would not lock up with the go gage. Barrels number 3 and 4 were a go with the go gage.
Testing with the other five bolts (with extractors in), None of the four barrels would close on the No Go Gage with any bolt. I found one bolt head that would not close with the go gage with any barrels. I found one barrel that I could get none of the bolt heads to close on with the go gage. One barrel worked only with one bolt. Two barrels headspaced good with three of the bolts.
Barrels number 1 and 2, if you use live round will the bolt lock up? Different brand ammunition will have slightly different headspace.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by Waffentag »

On barrels number one and two, it does not lock with the factory ammo that I have. However, I get good lock up with the 500 plush reloads that I sized to tight 308 specifications. I tested every single round in one barrel. So, I think that I can safely shoot these in that barrel.
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Re: More Dumb MG42 7.62 Headspace Questions

Post by Sw1ngK1ng »

When I set the headspacing on my mg the extractor ended up being about .01in. away from the face of the barrel so that should not effect your headspace. If it dose then I would take the barrel to a machinist or a really good gunsmith, explain how to headspace the barrel and have them do it. I imagine it would be a shot in the dark to find a random bolt that will match your barrel.

If you insist of buying bolt after bolt then this is this is the best price I have seen for them. http://www.robertrtg.com/store/pc/M53-B ... 186p81.htm
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Re: More Dumb MG42 7.62 Headspace Questions

Post by JBaum »

mg34 has them for $75 :D
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