Bending a straight bolt?

A

Aguila Blanca

Staff
A recent thread in the C&R discussion area ( http://thefiringline.com/forums/showthread.php?t=464659 ) brings me back to a nagging question. I much prefer the appearance of the bent (or semi-bent) bolt on the Mauser M48 to the straight bolt on the similar size M24/47. I keep wondering if it's possible to just bend down the bolt handle on an M24/47 to the approximate profile of the M48.

I know there are so-called "bent bolt" conversions, but they aren't really bent bolts. Those require sawing off the straight bolt handle and screwing on a new handle that's mounted on a tangent to the bolt body, rather then perpendicular and then having a bend in the handle.

And a straight bolt be bent?
 
Yeah they can be bent and if you're going to use open sights that's fine. Brownell's sells a jig to do it with but they really don't look too hot when you try to bend them enough to use a scope plus they're usually a lil too short for that.
 
yup. take the bolt out and completely disassemble. get some heat resistant grease (dont remember what its called) and smear it on all of the bolt body and inside on the threads, but not the bolt handle. heat about 3/4" from bolt body with acetylene torch until red hot. hook a wrench on the end of the bolt and bend! that simple. or you can buy a bolt bending block for mauser bolt and do the same thing but beat it with a hammer and shape for scope clearance. thats more for if you want a scope mount though. ill post pics of a spanish mauser that i bent the bolt for a scope.
 
For bolt changes you can cut and weld or bend . I chose to bend .Wrap bolt body with wet cloth ,heat with O/A torch and bend !
 
I went with the BB conversion a few years ago its not hard to do it right if you have the nessesary tools. My brother heated his with a torch and bent it.
I liked the way mine turned out in the end, my conversion bolt would move (wiggle) a little when the action was cycled. JBweld around the old bolt stub under the conversion fixed the problem! It's still solid to this day and I put several tins of ammo through it. good luck
 
I don't like the appearance OR the concept of whacking off a perfectly good bolt handle and screwing on an aftermarket abortion of a piece. I DO like the appearance of the M48 and 98 short rifle bent bolts, so that's what I would be trying to replicate. Scope clearance is not an issue -- scout scope.
 
Be a little careful .You do not want the heat to anneal the cocking cam surface of the bolt,that angled ramp at the rear of the bolt body.You also do not want to distort the internal threads in the rear of the bolt body that the cocking piece screws into.They do make a heat sink tool that screws in and supports the threadform.

I understand you do not need a scope bolt.Just an FYI,for a scope bolt,I hacksaw about75% through the root of the bolt handle,from the top down,at about the outer line of the reciever rail.

Then,I heat the underside quick with acetylene,and I have a red hot hinge to bend a square corner.I pull it down about 80-90 deg.

Now,where the hacksaw cut was made,it is opened up to a V to weld up.

We have actually gotten decent results with a little Lincoln fluxcore wirefeed.

After the weld is done,the knob can be bent out and even swept back a touch.
 
..I don't like the appearance OR the concept of whacking off a perfectly good bolt handle and screwing on an aftermarket abortion of a piece...
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No gunsmith "whacks off" and bolt hand, or screws on a replacement. The two accepted methods are to weld on a new handle, or bend the existing one. There are "bolt bending blocks" for sale that control the bending (forging). Heat stop paste is available from Brownell's or any welding supply shop to keep the heat from conducting down the bolt body to the locking lugs. This is a common procedure for gunsmiths, and knowledgeable hobbyists.
 
Those "screw on" bolt handles are a quick and dirty way to get low-scope clearance if you don't give a **** what the gun looks like. In fact it is easy to bend a bolt for scope clearance and get it to look good and be long enough if you know what you are doing. But you don't just use wet rags. You need a good heat sink inside the bolt as well (I used a foot long piece of copper ground rod) and if the bolt is blued, heat paste. (Much misunderstood, heat paste does NOT prevent the object from getting hot; it blocks the oxygen so the object doesn't burn at the surface.)

But the OP doesn't want a low-scope bolt, only a turned down one like the K.98k, and that is just a matter of heating the bolt handle and bending it, which is what the Germans did originally. The handles were forged straight, the bolt machined, then the handles hot bent to shape.

Jim
 
(Much misunderstood, heat paste does NOT prevent the object from getting hot; it blocks the oxygen so the object doesn't burn at the surface.)
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Horse feathers. Having used heat stop paste on several occasions, and when welding on a bolt handle recently, the past keeps the metal under it from even getting warm. I have felt the metal under the paste after welding to see how well it works. I am a former High School welding instructor and have demonstrated to my students that the paste keeps the metal cool by holding the part (a Mauser bolt) in my hand after welding, within two inches of the weld...try that without heat stop paste.
 
A lot of hobbyist and gunsmiths have bent bolt handles and done a good job.
However, a lot of bolts have been ruined too by improper techniques.
I've seen bolts in which the hardened cocking cam was softened, and several that had the rear of the bolt distorted by the heating and bending to the point where the bolt shroud would no longer screw in the rear of the bolt.

To do a proper job you really should use the heat-stop paste, a set of bending blocks in a big vise to help draw the heat away and support the bolt, and a copper heat sink screwed into the threads at the rear of the bolt.
This not only helps protect the surface hardened cocking cam, it also prevents distorting the rear of the bolt and threads.

A lot of bolt are ruined by damaging the surface hardening of the cocking cam.
After the bend, the owner is shocked when the bolt is difficult and sticky to operate. This is cause by the formerly hard cocking cam now being soft steel which is sticky under the pressure of operating the cocking cam.

Another good technique is as above to cut the bolt handle part way through near the root, heat and bend, then weld it.
 
Hi, Dahermit,

I would be interested in hearing your physics instructor explain how a thin layer of paste on the surface absorbs 1400 degree heat in a piece of steel. Maybe it takes a layer of horsefeathers will do that.

Jim
 
I would be interested in hearing your physics instructor explain how a thin layer of paste on the surface absorbs 1400 degree heat in a piece of steel.
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Physics instructors will explain that evaporation is a cooling process. What ever the "wet" substance is in the paste evaporates and the paste turns into a powdery residue where that heat gets to it. A "thick" layer of paste is used. The melting temperature of steel is approximately 2700 degrees not 1400. Other than that, holding a typical Mauser bolt in ones hand immediately after welding on a bolt handle will convince anyone...well maybe not you. As I have stated, I have done it using Brownell's Heat Stop Paste, and I am sure many others on here will have done it also.
 
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