NO4MK1 bolt heads

sunray said:
"...to get the barrel torqued..." Whatever for? If the barrel is loose, you have far greater issues than headspace. You need a barrel vice and action wrench, a proper action wrench, to fix it. A local hobbyist is highly unlikely to have or want to buy the proper tools to fix a Lee-Enfield barrel issue. And don't let anybody near your rifle who says it can be done with vice grips or a pipe wrench.
Marstar is listing No. 4 bolt heads at $19 each. They're listing 0's, 1's and 2's.
I'd be inclined to spend the money and buy a set of headspace guages. Brownell's.
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The barrel was loose when i got it, someone had tried to put it on but i think they over torqued it, the barrel was kinda mushroomed, hes been in the buisness for 30 years has alot of the tools, i just found out theres another guy has a barrel vise and the proper wrench, but any way when you tightened the barrel the sights were off, so it needed to be shimmed,
 
I'm no gunsmith but it sounds like you're getting into a big project for that barrel.

Thanks much for the headspace tip!! I'm going to check mine today.
 
So if your bolt head turns say 45 degrees then what? New bolt head or maybe a thin washer between the bolthead and body??

The idea is when the bolt handle is turned and the bolt is in battery the head should be snug with the bolt body? Figured I'd ask as one of my lee enfields has more travel in the bolthead then I would like, I only shoot light cast rounds through it and well it's deadly accurate but I'd like to take the slop out of the head. It turns like 30-40 degrees which is way to much.

Any suggestions while we're on the bolt head topic.

Oh and I'll add that Winchester 30-30 is a REAL nice guy he probably won't name the crappy gunsmith publically even if you beg.
 
thank you tinman, im not going to name, just that he was crappy, i dont think the bolt head turns past, he said the headspace was no good, this is the first time ive ever used this guy, locals have suggested him, but never again, my "JUNK" so to speak isnt good enough for him to work on
 
Correct bolt head fitting isn't just a matter of having the head index within limits on the bolt body. Firing pin protrusion is also an issue which must be checked. Here's what Cdn Army EMEI says about it; " test the bolt head for over-turn which will not exceed 20 deg. With the cocking piece in the long cam groove check the lift by screwing in the bolt head. Correct fitting is ensured when the final turn of the bolt head pushes the cocking piece back 1/64 to 1/16 in. This distance will not be adjusted by backing off the striker from the cocking piece, but by interchangeing components". There are enough bolt heads in circulation that a person should be able to check a few of them for both correct fit and correct headspace by trial fitting a few different ones. if you are shopping for bolt heads at a gun show, its a good idea to take the bolt along to be able to trial fit a few different bolt heads before buying one. If a correct bolt head cannot be located, one could also experiment with different bolt bodies subject to the proviso that there is correct bearing of the locking lugs in the action seats.

The comment about the barrel being "kinda mushroomed" on the receiver is a head scratcher. If there was so much torque applied to deform the barrel shoulder to a noticeable degree, I'm surprised that the receiver ring was not cracked in the process. I did my first No4 barrel install back in the mid-70s under the supervision of the late Tommy Richardson, a DCRA and Bisley shooter of some note. I recall pulling on a real tight one when Tom took over and put a cheater bar on the wrench and actually dangled himself clear of the floor in the process. Tom was a slight man, but that was still a lot of torque. That barrel timed up just fine and has been a good shooter ever since.

A No4 barrel which fits too loosely can be shimmed to get the right amount of torque for installation. The military provided .002, .003, and .004 thick breeching washers for this purpose with the stipulation that .004 was the maximum thickness to be used and that only one washer would be used. Co-incidentally I have a project to install a NOS barrel on a M1903 Springfield receiver where the initial barrel/receiver fit is too loose to get a proper degree of torque when the barrel is indexed to top dead center. I have a set of steel shim washers inbound with the intention of using one of the correct thickness to get a proper fit. I ordered the shim washer set from a hobby car parts supplier.:cool:
 
A bolt head wrench was used to fit the bolt heads, meaning the bolt head should stop rotating with your fingers "before" it aligns with the long bolt lug. The wrench was used to break in the fit by working the two parts together until they aligned.

The British also used "bolt head timing" when fitting the bolt head, properly fitted the rear of the bolt head did not touch the collar on the firing pin until the last 90 degrees of bolt head rotation. Looking from the rear of the bolt contact should be made at the 3:00 position and stop at the 12:00 position, and allow the bolt to close without binding on the bolt head. Maximum wear rotation was 20 degrees past the locking lug and tighter is better.

The Canadian manuals simplified this to allow for greater wear on these older No.4 Enfield rifles used by the Canadian Rangers and just give a gap tolerance between the rear of the bolt and the cocking piece. This works out to be approximately the 5:00 position to the 2:00 position. (less demanding specifications)

 
igot the gun and it was loose when i took it apart to see what i got, the ring for the rear handguard was gone, so id assume they took it off to get that ring off, barrel serial does match the receiver, im pretty sure the bolt is good, i was only concerned with headspace as i got the gun the bolt was missing so i purchased one, then all of this took place, i gave him another bolt from my parker hale sporter with a no1 head to check it,
 
Winchester30-30 said:
The barrel was loose when i got it, someone had tried to put it on but i think they over torqued it, the barrel was kinda mushroomed, hes been in the buisness for 30 years has alot of the tools, i just found out theres another guy has a barrel vise and the proper wrench, but any way when you tightened the barrel the sights were off, so it needed to be shimmed,
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Either someone has cut material off the barrel shoulder or off the face of the receiver ring, or if it is significantly "mushroomed" the shoulder has been damaged by extreme over-tightening.

You're best to turn a new shoulder on the barrel and make a breeching-up washer. You can lap the washer to whatever thickness you need to make the barrel come up just right by hand. You have to be careful to keep it dead square when lapping though: emery paper on heavy plate glass for example.
 
RRCo. said:
Either someone has cut material off the barrel shoulder or off the face of the receiver ring, or if it is significantly "mushroomed" the shoulder has been damaged by extreme over-tightening.

You're best to turn a new shoulder on the barrel and make a breeching-up washer. You can lap the washer to whatever thickness you need to make the barrel come up just right by hand. You have to be careful to keep it dead square when lapping though: emery paper on heavy plate glass for example.
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I'm really surprised that the reciever didn't crack. Im no gunsmith but a barrel is pretty hard steel and it would take a significant amount of force to destroy the end of it I should think. What if the barrel was loose and the gun was fired that way? Maybe that would be enough to mushroom the barrel?

Maybe just get a new barrel and call it a day, may be cheaper/easier/safer in the end??
Just my thoughs.
 
You just never know what you will run into with old MILSURPs which have been away from military technical surveillance for many years with many and sundry opportunities for civvy owners to #### around with them. I recall a guy at a gunshow telling me about his Garand having a loose barrel. No fear though because he was going to tighten it up with some teflon plumbers tape. I suggested that this was a very bad idea :rey2, but he thought he might just try it anyway. Fortunately I never did find out how that worked out for him. G:
 
Winchester30-30 said:
its been shimmed, and tightened up, so long as the headspace is good on this new bolt, i dont see a problem in firing it
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Good. Remember that bolt locking lugs have to be lapped in or at least inspected with layout blue to make sure they contact evenly for accuracy reasons if no other.

The small lug has been known to crack, especially with wet ammo when the bearing was not even. Not often, but it has happened. For the benefit of anyone who might be concerned, as far as I know there is no danger to the shooter if that should happen, just a PITA.

I should clarify my previous comment about setting up the breeching washer so that the barrel "just comes up by hand". I don't mean it comes up to the final position, but rather about 15° before it, to allow for final tightening with the barrel wrenches.
 
I just had a #5 barrel put into a #4 receiver on Friday. It took a 5 thou shim and headspaces to 0 bolt head. It's the only thing that I can't do myself as I don't have the tools to change out a barrel and do so so rarely that it is not worth the setup. Changing one without the right set-up can ruin a good receiver.
 
In the early 1950s Springfield armory developed a technique to salvage and re-use M1 Garand receivers which allowed the barrels to over-index before tightening. What they did was to chrome plate the face of the receiver. It must have been an interesting operation to confine the chrome to this specific area as chrome plating is done electrically with the item immersed in solution. I had a Winchester Garand receiver which had been reclaimed in this way. I don`t know if this was ever attempted with any other kind of rifle, but it did work. I didn`t understand what it was at first until I parkerized the receiver and saw that the receiver face remained bright. I re barreled this one and it worked OK.
 
RRCo. said:
Remember that bolt locking lugs have to be lapped in or at least inspected with layout blue to make sure they contact evenly for accuracy reasons if no other.
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Lapping the locking lugs on a older Enfield could be adding insult to injury, lapping the lugs could be just enough to wear through the heat treating of the receiver and end up into softer metal. This is why bolt heads only went to a number 3 bolt head, it was found that by the time a Enfield needed a number 4 bolt head the heat treating had worn through.

If a rifle failed headspace testing it was checked with a test bolt of a known length and a specific length number 3 bolt head, if the bolt closed on a .074 gauge the the rifle was sent for FTR or overhaul.

Below is a fired case from a No.4 Enfield that failed headspace testing with a number 3 bolthead, the amount the primer is protruding is head clearance or excess headspace the rifle had with a number 3 bolthead.



The owner of this Enfield was a machinist and he added a threaded extension to his bolt head, silver brazed/soldered it in place and re-heat treated the bolt head. Because the heat treating was worn through on the receiver this rifle was only used for light cast bullet loads.

 
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