GI barrel headspace issue

[JBishop]

If this is the wrong place to post this question I apologize. I am rebarrelling a rifle with a used GI barrel. Receiver is a Winchester GI. The barrell is clocked right but the head space is off. The bolt will not fully close. It seems I need to ream the chamber. Is this a common thing? Is it a chamber issue or something else possibly? I am kind of at a loss because I figured the chamber would be correct. To clarify, it will not close on a dummy round/snap cap. I haven’t got a go-gauge but I ordered one. Thanks for any advice.

Jon

[jak]

A snap cap is NOT a substitute for a proper gauge. Remember to disassemble the bolt before using the go-gauge.

[JBishop]

Thank you for the reply. The bolt is disassembled. In all honesty I tried it with a live round. The bolt still didn’t lock. With no round in it locks just fine, of course. My gauges will be here monday. I actually bought a go and no-go gauge. The bolt seems original to the gun, WRA. The original barrell was horrible. You could probably drop a bullet through it. It also had a bad spot in the chamber and the casing would not eject. I had to hit the op-rod with a plastic mallet to eject the round. There was a big scar on the right side of the brass. Aside from that, every thing is in working order. The question is still; Is it common to headspace a used GI barrell?

Thank you, Jon

[jak]

The question is still; Is it common to headspace a used GI barrell?

Yes, You should check headspace any time you change a barrel or bolt. There could be wear on the bolt and/or receiver which could change headspace. Also, different revisions of bolts had different lengths which would change headspace.

[Orlando]

Yes you should always check head space. I have never found short head space on a used barrel but anything is possible. Are you sure the chamber is clean? You should clean it thoroughly with cleaner and a chamber brush the wipe dry with patch before checking with gauges

[Smokey]

Headspace is always carefully set for a given barrel, receiver and bolt by finishing the chamber on a short chambered barrel. If any of those three items are changed, the headspace will be suspect. At risk are cartridge failures (gas leaks) from excessive headspace, or slam fires from inadequate headspace, which can blow the rifle apart.

[JBishop]

My go-gauge came in and it seems I’ll need to ream the chamber. Do you have to use a pull through reamer? Will a regular reamer work? Should I try another barrell? Thanks for the replys.

Jon

[jak]

What bolt are you using ? You might be able to swap out a bolt instead of reaming the chamber or swapping another barrel to achieve headspace.
Here is a list of bolts from shortest to longest.

WRAs
-12SA
-14
-17
-19
-2
65-series

I use a pull through reamer

[JBishop]

I don’t see any of those markings. Here is a picture of the bolt.

[jak]

The list I posted shows the that the WRA bolts are the shortest bolts. The others are Springfield Armory bolts with the 12SA being the shortest of the SA bolts but longer than the WRA bolt. Sorry for the misunderstanding.

That is one gnarly looking bolt. I never saw a chunk taken out of the rear of the bolt like that.
It might be ok or not, but I personally wouldn't use it. Maybe others could give their opinion on that bolt.

[JBishop]

The picture makes it look worse than it is. It’s not a chunk missing, just some pitting from rust. I bought this rifle about 12 years ago. The guy had a story that it was found at White Sands missle range in NM. Whatever I said. It certinally looks sanblasted. He also told me the barrell was bad. I did test fire it after I brought it home and decided it was sound to shoot. There is other pitting on the rifle. Mostly on the op-rod and some on the receiver. The op-rod is good though. It’s the charging handle where the pitting is. I’m not worried about that. I just want to make this a shooter. My other M1 is just too pretty to shoot. I’ve sold off my other shooters awhile back. With regards to reaming though, can I use a standard reamer with the receiver and barrell together?

Thanks, Jon

[jak]

I don't know, I only use a pull through reamer.

[Smokey]

I would not use that bolt. Keep it for a curiosity item, but find another one in better condition. Have the bolt to be used inspected for any cracks and flaws, then CAREFULLY ream the chamber to set the headspace. Better yet, take it to a gunsmith and have the headspace done by a professional.

I have to ask, WHY are you replacing the barrel?

[jak]

I have to ask, WHY are you replacing the barrel?

Read post #3

[lapriester]

In virtually EVERY case you will have to headspace ream ANY new barrel installed. Thinking because it's a USGI barrel that headspace will be correct is totally incorrect. The odds of that happening are probably less than 1 in several hundred no matter what bolt you try. I have personally installed more than 2 dozen new barrels and have yet to have one headspace without reaming. BTW-If for no other reason except it's questionable appearance and condition, you need to replace that gnarly, ugly, pitted thing you're calling a bolt. Headspacing with that will probably create more issues in the future. New barrel, gnarly bolts are never a good combination.

If you don't have headspace gauges you absolutely must purchase at least a Go gauge. There is no place using, brass, snap caps or guesswork when headspacing a Garand barrel. Get it wrong or get it short and you risk an out of battery slam fire and it won't be a pleasant experience. Short headspace increases the possibility of one by 10X. Anyone who says different is putting your safety at risk. Pull through reamers can be rented. Google it. Buying will be prohibitively expensive if you don't plan on doing multiple installs.

If you don't have the right tools or have to make assumptions on correct barrel installations you need to refer the work to a professional who knows what they're doing. Your original post tells me that it's something advisable for you.

Here is a link to instructions for Garand barrel installation. Carefully following them and having the correct tools will make your work successful snd safe.

https://www.dropbox.com/s/3hayif5mh4...B1%5D.pdf?dl=0

While your at it, do this in the process:

https://www.dropbox.com/s/ym9hk7qq7v...B1%5D.pdf?dl=0