Grendel and .473 bolt face

[se3388]

I was sitting around pondering things (gets me in trouble more times than not) and was thinking about the idea of taking a regular bolt (.473) and soldering, tigging, silver soldering or however attaching a ring to reduce the bolt face down to take the 6.5 Grendel. Has this been tried by anyone here or is it even feasible?

Steve............

[cory]

You're talking about a device that is designed to contain an explosion of 52+ ksi. I wouldn't suggest this.

[mongoosesnipe]

You have to open a standard bolt from .373 to .445 not reduced so I am not sure what your planing to add to the bolt and for what plus you have to modify the ejector and extractor as well I played around with it earlier this year it's a hassle and unless you have the proper tools it's not even worth trying

[Tedward]

Even is you modify the surface on any bolt, whether you machine a 7.62 bolt deeper or open up and deepen a .556, you are removing the surface hardening. I have been talking to the bolt manufacture guy, M.F., and when a bolt is hardened, it is to the surface, not throughout. Then it is shot peened to harden the surface further. He explained it is like taking a million tiny tiny ball peen hammers and hitting the hardened surface to creat smashed hardened surface. SO, if you alter the surface in any way, you are removing the material hardened surface and you weaken the bolt.

Don't mess with them, buy the correctly manufactured and finished product. OR risk you safety.

[se3388]

My bad, I meant .473 and NOT .373 bolt face.
Cory,
It contains the pressure anyway even before adding material to it but your answer was before I corrected my bad with the dimensions.


Tedward,

I was thinking that something like silver soldering a small bushing into it might not get it hot enough to change the hardness but I'm not a 'smith' so I don't know. With something like a Remy bolt you could notch the bushing and the ejector would probably work with the Grendel case, maybe.



Steve............

[mongoosesnipe]

My bad, I meant .473 and NOT .373 bolt face.

Steve............

[LRRPF52]

The .473" diameter is for the .30-06 and .308 case head families, not the Grendel. The Grendel uses a .441" case head diameter. The bolt head is a little wider. I just measured one at .447"

The Grendel bolt is a complete re-design, since you need to account for other things than case head diameter. Extractor geometry being a key consideration.

[nincomp]

I was thinking that something like silver soldering a small bushing into it might not get it hot enough to change the hardness but I'm not a 'smith' so I don't know. With something like a Remy bolt you could notch the bushing and the ejector would probably work with the Grendel case, maybe.

I hope that you only mean for bolt-action rifles. In that case, no soldering is needed on some bolts. The .473 bolt for the Savage 10 and 110 series only needs a different extractor.

[JASmith]

The .473" diameter is for the .30-06 and .308 case head families, not the Grendel. The Grendel uses a .441" case head diameter. The bolt head is a little wider. I just measured one at .447"

The Grendel bolt is a complete re-design, since you need to account for other things than case head diameter. Extractor geometry being a key consideration.

My experience has been similar to this. I have used a .473 bolt face for my initial load work up in the .20 Grendel in a Savage Model 16. The main challenge is that the extractor does not always grab the rim so the old cleaning rod gets exercised.

So, yes, pay attention to the extractor details.

Note the the 7 mil tolerance between the rim and the sides of the bolt face. Further, the base of the cartridge is not entirely supported by the chamber wall, so if the rim expands to meet the sides of the bolt face, brass will already be seriously flowing in other places.

[se3388]

LRRPF52
I was talking about bolt action rifles, I know what cases go with what bolt heads.

nincomp
Sorry I should have stated in the original post it was for a bolt action. I think JASmith has experimented along the lines I was thinking about except for working on the bolt head.

JASmith
I am wondering if it would work better with a slightly longer lip on a claw type extractor, might not work as well with a plunger style ejector. My original question was, is or has it been done to attach (welding, soldering etc. etc.) a small bushing of some type to bring the bolt face down to .447 from .473? I know you can swap bolt heads on Savage rifles but I was thinking about other types of bolt actions.

Steve............

[JASmith]

Steve,

I am reasonably sure that the size of the bolt head is not an issue. There is an illustration showing why in the discussion on using your brass to infer safe pressures. Scroll down a ways until you get to the cross-section view and you can see that the case is not supported from about midway into the web all the way back.

BTW The methodology did not work for me -- I think my brass is too strong to even begin to move at Grendel pressures. Nonetheless, it helps make the point about not needing a tight fit on the bolt face.

You do need, however, to have an extractor claw that will properly grab the rim of your case.

[hm2 clark]

Gunsmiths have been opening up the bolt faces on 98 mausers for over a century. I have seen 98 mausers for sale that were opened up to 7.62 x 39 so it probably is doable.

[LRRPF52]

Sorry. Failure to read on my part. I was thinking AR15 for some reason, even though this is in the Bolt Gun threads.

[nincomp]

A lot of benchrest competitors use Remington receivers for their 6mm PPC rifles. The PPC has the same base diameter as the Grendel. If you can find a site for benchrest shooting, you may get your answer.

JASmith, Sharp Shooter Supply sold an extractor to allow a standard Savage bolt to work with the 6mm PPC. They might still sell it.

[JASmith]

...Sharp Shooter Supply sold an extractor to allow a standard Savage bolt to work with the 6mm PPC. They might still sell it.

Alas, I checked this afternoon for my project and found that they no longer sell the PPC extractor.

One can buy a PPC Bolt Head. Swapping the bolt head is only a little more involved than swapping the extractor and, for Savage owners, the question of face diameter is moot.

[nincomp]

a
One can buy a PPC Bolt Head. Swapping the bolt head is only a little more involved than swapping the extractor and, for Savage owners, the question of face diameter is moot.

Sorry about that. As you were writing your response, I was checking out the Savage Arms site. I was not sure that they sold the right diameter bolt until I discovered that their Scout Rifle is now sold in 7.62x39.

[JASmith]

The Scout rifle is not a bad start if you want to go Grendel or a Grendel Wildcat.

[GLShooter]

PT&G makes Grendel sized Savage bolts. Bushing Remington bolts is a no brainer for a benchrest gunsmith for 6PPC/Grendel cases.

Greg

[nincomp]

What is involved is bushing the bolt?
Thanks.

[se3388]

GLShooter
That's what I was wondering, are any modifications needed to the ejector?

Steve............