How did this bolt face get so mangled?

[buzz]

This is a bolt from a very early Savage, serial number in the 17,000 range.

 

No idea if the bolt is original to the gun or not.

 

The bottom lip of the bolt face is very battered and distorted, like it got peened out of shape by smacking something repeatedly.

 

There's nothing in the barrel or on the feed ramp that would have done it, both look perfectly normal.

 

Maybe just a bad bolt?

 

Ever seen this kind of thing before?

 

 

Also, this bolt is made from some sort of chrome or nickel steel, it's almost like some sort of stainless. But there would be no reason to use stainless and I'm pretty sure it wasn't used for gun parts until like 1970 or so.

 

If it's just bright carbon steel it should have some traces of atmospheric corrosion on it somewhere, which it doesn't. And it is not any sort of nickel plating that I ever saw.

 

 

 

 

Edited October 6, 2014 by buzz

[darrylta]

Buzz,

I think the bolt is of a high nickel content steel made to fight corrosion and add durability to parts. The original Colt's used

this type of steel in most of the internal parts of the trigger frame and receiver parts.

 

In the past most collectors used the term "nickeled" which to me inferred that the part was plated.. Not so, again it's a high nickel

content steel. I got confused with the terminology myself when I first started collecting Thompsons.

 

Your bolt looks to have had many, many jams in it's past.

 

My 2 cents,

Darryl

[giantpanda4]

Not jams, probably was in a Dewat with weld in the barrel. I had one like that where the bolt slammed into the weld puddle and it looked the same.

 

Where did it come from?

[TD.]

I believe giantpanda4 is spot on. And I know he has some experience with dewats. Model 1921/28 Thompson bolts are nearly indestructible. The end of this bolt has obviously been hitting hard on something, probably for a very long time. It is certainly not indicative of normal use. Perhaps reconbob could comment on the normal life of a bolt in one of his post sample range guns.

 

I would not use it under any circumstances.

 

I too have used (in the past) and heard the term nickeled. The more correct term or description is "bright."

[bug]

Looks like a typical S bolt. If it's not hitting anything on the ramp or stopping the gun from going into battery it will work. That said, I'd replace it with a "new" one and save it as a spare. Parts is parts. I've seen bolts used as punches or hammers, mags used as pry bars etc. Dropping onto a concrete surface can do a lot of damage to slender sections of heavy parts. It really doesn't matter how it happened or how it got into your gun. As TD points out, it's not normal wear and per Panda, take a real good look at the breach for signs of dewat.

[Banjo]

Saw one similar to that, the owner was embarrassed, said he'd had a bullet in the chamber that had not gone off, without thinking he pulled the bolt back and pulled the trigger again. The second bullet discharged behind the first bending the lip of the bolt out. This guy then used a hammer on the bolt to try and bend the lip back enough to work. The end result looked alot like yours.

[buzz]

The bolt came out of an early Savage 1928.


There's no way to tell if the bolt is original to the gun or not or what sort of use the bolt has seen.

The gun appears to have the original finish and has the kind of wear associated with normal use. I don't see any signs of excessive wear or abuse to the gun.


I don't believe the gun is any sort of dewat, there is no indication of that whatsoever. The feed ramp and breech end of the barrel look perfect.

Also, it would appear that I'm the first private owner of this gun, it was purchased in 1980 by a police supply company from a gun wholesaler.

It was purchased as a pair with a police-marked M1A1. I think that the 28 was probably one of the fabled police owned Savages.

I have a FOIA letter in for both guns, probably will get an answer around the same time the glaciers return to terraform north America.


I guess there's no way to tell what happened to the bolt.


What I was wondering is if bolts are ever seen to deform in this way through normal operation of the gun.

Which it appears not.

Edited November 9, 2014 by buzz

[reconbob]

In my "travels" I have seen about 5 or 6 bolts with this damage - where the rim of the bolt face

seems to get battered and deformed just like the photos. About half of them have come thru in kits

and the other half I have observed in guns. One of the guns was a M1921 Thompson which has been

in possession of a local police department forever (so it is not and never was a DEWAT) and on this

gun, if I recall, the damage was so bad that part of the rim had cracked away.

I never gave this much thought, but now that Buzz has brought it up again, I can't imagine what

a bolt would be hitting that would cause this damage. I don't think this would be caused by the bolt striking

cartridge cases because a steel bolt is so much harder than a brass case.

I will make an educated guess - if you are using a gun in which the bolt hold-open on last shot is

not working (trip, disconnector, sear lever) the bolt will strike the steel magazine follower and I think

this, over time would damage the bolt.

You can check this by putting an empty mag in your gun and slowly retracting the bolt. before you

get to full cock the mag follower will snap up in front of the bolt face. However, the follower would hit

the left side of the bolt rim and Buzz's bolt looks to be damaged in the middle and right. Maybe a

magazine with damaged feed lips would cause this....

 

Bob

Edited October 7, 2014 by reconbob

[reconbob]

More thoughts - I can recall in the course of doing builds encountering bolts with Buzz's

defect, but where the damage was slight enough that I could stone the rim smooth and

the bolt was ok. Also, I do not ever recall seeing this damage on an M1 or M1A1 bolt.

There is a cause for this and now even more I am wondering what it is. I do not think it

is due to cleaning rods. You'd have to really try hard to damage a bolt like this while

cleaning the gun.

In my opinion this is the result of the bolt hitting something during firing or dry firing.

As opposed to cleaning, assembly, disassembly, etc.

I'll bet the police armorer still has the broken M1921 bolt - I'll see if I can get it to

photograph.

Bob

Bob

[TD.]

Bob,

I don't think the thin metal follower of a Thompson magazine could damage a bolt like what appears in the picture. In addition, I don't think the bolt would travel far enough or fast enough if hitting a follower. Continuous dry firing may be the culprit, like a child playing with a toy. If the cause was excessive dry firing, i.e., continuous slamming the bolt home on an empty chamber, would the bolt most likely damage the barrel (given the obvious damage to the bolt)?

 

Great discussion!

[buzz]

Ok, I just spent an hour goofing around with my thompson.

 

The feed ramp and the breech end of the barrel are completely smooth. See photo. The barrel has a bright chamfer on it, there is no sign of any sort of impact on it.

 

I tried Bob's suggested experiment. When the bolt is drawn back slowly, the mag follower clears the bottom of the bolt and then pops up in front of the bolt face, but if you keep pulling backwards another 1/8 inch or so the bolt locks open as designed. It's obvious that the bolt is not being restrained or impinging on the magazine or follower. If the magazine is removed, the bolt stays locked back unless the trigger is pulled.

 

Also, if the bolt was striking the follower, the big divot in the bolt face should be on the left but it's on the right.

 

I don't think the gun was dry fired, the guy I bought it from is an serious collector. He actually cautioned me to not dry fire the gun when i picked it up, he said it would "mess up the headspace". Does the bolt face strike the end of the barrel or feed ramp if dry fired? i would have thought that the body of the bolt would strike the receiver before the bolt face hit the barrel. You'd think the designer of the gun would make sure the bolt energy wasn't absorbed by the bolt face by smacking the barrel. Plus you can see that the bolt shoulder makes hard contact with the receiver when the bolt is full forward.

 

If there's some malfunction or flaw with the gun, I have a self interest in discovering it so it can be corrected. But I just don't see anything that could be peening the bolt face. it looks like somebody hammered nails with it but there's nothing in the gun that corresponds to the bolt damage.

Edited October 7, 2014 by buzz

[laurencen]

just my opinion but it looks like it hit a round object off center that had a hole in it like a shell casing, appears to be a single hit or many in exactly the same position, possibly taken out of the gun and dropped on its face?

[reconbob]

I realize now that the answer is right in front of us. Buzz's bolt is soft. For it to deform the way it has
it would not be possible for it to be hard. If it was hard it would not deform - pieces of it would
crack off. The fact that the steel is "flowing" or denting shows how soft it is.
I can certainly see this happening. The M1921 Thompson was made in 1921 and 1922. Now, only
3 years before this Springfield Armory was grappling with the problem of M1903 rifles failing due to
cracking receivers and bolts. If you care to read about it there is an entire chapter devoted to this
in Hatchers Notebook. The bottom line for us here is that the receivers and bolts were heat treated
by workers considered to be master craftsmen, but using no scientific equipment because such
equipment did not exist - had not been invented yet. The workers used the color of the heated steel
to judge and determine the temperature. Of course this was very inaccurate depending on such factors
as whether it was a bright sunny day or a dull cloudy day as back then big windows and daylight
accounted for much of the light on a factory floor.
In 1918 temperature testing equipment was installed and it was found that the master craftsmen
were often way off in determining correct temperatures. The heat treatment of the M1903
was changed in 1918 (the high number "double heat treat" receivers) and there were no more problems.
So here we are at the Colt factory only 3 years later. It is quite possible that Colt did not yet
have a scientific set up yet but was relying on the old color scheme for heat treating. Regardless we
see that some bolts got thru with soft rims which deform under use.
If your old bright bolt made it this far you probably have a good one. If not, it probably failed
already. This might explain why we see so many M1921's with military bolts and actuators. The original
bolt failed, and way back the guns were not valued as they are today so you put in a military bolt and
actuator and moved on. Considering the value of a Colt I would not shoot it with an original bolt. If by
chance your bolt should fail you can't go back and you can't get a replacement. Shoot it with a military
bolt and save the original bolt for when its back on the wall or in the safe...

 

I dug out a M1921 bolt from my parts reference library. I did not take this out of a gun, it showed up

in a batch of parts sets. It is starting to fail:

 

http://i51.photobucket.com/albums/f392/reconbob/IMG_5421_zps51045c17.jpg

 

http://i51.photobucket.com/albums/f392/reconbob/IMG_5422_zpsd2d5110b.jpg


Bob

Edited October 7, 2014 by reconbob

[buzz]

Bob, have you seen any blued bolts that have deformed this way?

Edited October 7, 2014 by buzz

[TD.]

Bob,

With all due respect, I don't "...see so many M1921's with military bolts..." I do see some, usually ones that are not complete, mix-matched, re-blued, re barreled and classified as shooter grade for one or more reasons. Actuators are another story, especially the 1921 style actuators. All this said, what happened at Colt's in 1921 and 1922 would have very little to do with a bolt manufactured by Savage Arms in 1940 - unless we had numerous examples of this problem during the war years. Even a few documented problems or failures with the hardness of the bright bolts would help. Unfortunately, I have never heard of this type of problem. What I do see are tons of 1928 bolts on the market, many brand new in the wrap. That tells me 1928 bolts do not wear out very often.

 

It is plain to see the nose of this bolt has been banging into something. If continuous slamming against an empty chamber would not cause this damage then continuous hitting of a plug of steel welded in the barrel would be a likely reason. Debunk this simple explanation and I will get out Hatcher's Notebook.

 

A great discussion!

[emmagee1917]

How about clipping the edge of the hole between the bolt pocket and the mag well ?

Chris

[reconbob]

Hey T.D. -

I have not handled many M1921 Thompsons, but I'd say 1/4 of them had military

bolts in them. Now, this could be explained by the really good guns being out of circulation in collections and not

sitting on tables at guns shows for me to be able to look at.

As far as the time line of the bolts - I agree. The bolt I have is a Colt bolt. The bolt Buzz has is a 17,000 range

Savage. I do not know when that would have been made and certainly the state of the art for manufacture was much

more advanced in 1940 that it was in 1921.

We have two soft/deforming M1921 bolts. The one I have and the one from the PD.

That bolt was so badly damaged that the new armorer took it to the welder down the street to see if they could weld

it for him and they sent him down to me. This police gun is not and never was a Dewat so the plug in the chamber

theory does not apply to that bolt, or to Buzz's bolt.

According to the drawing the hardness of the front rim of the bolt is Rockwell C 62-70. That is hard. My belief is

that at that hardness (harder than a Garand receiver and almost as hard as a file) you are not going to get the plastic

deformation (i.e. the denting or bending of the steel in such a way that it stays deformed and does not spring back)

you would get cracking and the breaking off of pieces. So the fact that we are seeing this bend-but-not-break deformation

shows that the steel is not as hard as it should be - again, my opinion.

When a gun is dry fired the bolt face does not contact the rear face of the barrel. The front face of the rectangular body

of the bolt hits the front of the bolt pocket. When cartridges are fired the case acts as a shock absorber and you do not

get the steel on steel slamming.

I do not know if I am debunking this damage being caused by dry firing Dewats with steel plugs in the barrel, but

we know that 2 out of the three bolts in question are not in Dewats, but in working/shooting guns. Also, I have noticed

these damaged bolts coming thru in the parts sets which were also not Dewats.

All this being said, still the question is, even if the bolt rims are too soft, they are still steel and what is causing this

damage? Could the feeding of brass cartidges over time deform the rim of the bolt face if its not properly hardened?

I will keep my eye out for more damaged bolts and I would encourage anyone who has one or finds one to weigh in.

 

Bob

[buzz]

It's easy to see the feed ramp and also feel the entire feed ramp with your finger.

 

I'm telling you for true that the feed ramp is perfectly smooth, uniform and symmetrical and it shows no evidence of any kind of interference with the bolt.

 

The barrel shows a light chamfer all around and is mated neatly with the receiver feed ramp.

 

If the bolt was damaged by clouting some obstruction, it did not happen in this gun.

 

 

On the other hand, based on the published rate of production for 1940, this gun would have been made in the first maybe 8 weeks of production.

 

Could it be that Savage wasn't quite up to par on Thompson bolt manufacture when this gun rolled off the assembly lines? Maybe the heat treatment was not up to spec.

 

Of course it could also be that the bolt might not be original to the gun.

Edited October 7, 2014 by buzz

[darrylta]

One reason people see GI bolts in Colt guns, is that they are being frugal. Replacing the original bolt with a GI version thinking they are preserving

the bolt and the gun outlives them in this modified state.

 

I have several Colts that are in this state, it's on my to do list to put the original bolts and hardware back in the guns.

It's a recurring nightmare that my heirs wouldn't know and sell the guns as is, with the Colt hardware in an unforeseen parts box.

 

My 2 cents,

Darryl

Edited October 7, 2014 by darrylta

[buzz]

Bob makes a very good point about the chipping vs plastic deformation.

 

Hardness of 60 is in the range of cutting tools like real high quality scissors or a common metal file.

 

You'll never see a pair of professional grade scissors with a dent in the blade but you'll see plenty of them with the blade snapped in half from being dropped.

 

Is it possible to harden that little lip on the Thompson bolt to 62 to 70 and then also have it flow like putty from sharp impact blows?

 

Who's got a hardness tester?

Edited October 7, 2014 by buzz

[laurencen]

I have a hardness tester but too far away, if you have a local machine shop they would have a sample kit of hardness strips, you can get prety close comparing a scratch test between bolt and test strip, even if it was not thro hardened the outside would show stress cracking

[bob241]

This may be the answer to the bolt face lip damage, as per american thunder II, page 449-450.

By june of of 1943 over 1 billion rounds of steelcase 45 ammo had been produced by Frankford Arsenal, shortly after the steel cased .45 ammo was issued it was discovered that the bolt faces of some Thompsons were being damaged, more specifically, the damage was to the lower portion of the bolt face lip.It was found that the damage was a result of the steel cased carridages jamming on the weapons feed ramp. To remedy the situation, a special reamer was designed to chamfer the radius around the chamber to allow more reliable feeding of the cartridges.

Edited October 7, 2014 by bob241

[buzz]

great thread

 

bob241, very interesting. Did it say what sort of damage was done?

 

I wonder why a steel case would jam on the feed ramp? It's a very shallow and slick ramp compared to most guns. I guess the case rim was catching on the barrel if they used a chamfer to fix the problem.

 

 

ETA -

 

The more I think about this, the more sure I am that Reconbob is right.

 

Is there any possibility that a thin lip of metal like that could be hardened to 60 and then flow like putty?

 

Get a cheap rat tail metal file from the hardware store and try to peen it with a hammer to look like that bolt. It'll just chip and crack.

 

Also, you can see in the picture I posted that the feed ramp is perfectly smooth.

Edited November 9, 2014 by buzz

[JimFromFL]

I can image someone having the Thompson dismantled and used the bolt as a tool and the marks have nothing to do with normal functionality. Just my 2 cents.

[ThompsonCrazy]

Not the greatest pictures but looks like this bolt suffered the same fate.

 

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=454197288

 

TC