Need the size of the face of a bolt.

Built a Grendel on a Charles Daly. I don't think that the smith opened the bolt face enough.

Mine measures .439 and the brass measures .440. My thinking is that it should be around .443.

Any help would be appreciated.

Opened the face from what?

A 5.56mm Bolt? :eek:

Deakin, be careful, bro. The 6.5 Grendel recoils more than 5.56, so I wouldn't trust a 5.56 bolt machined open for a 65G. Is it possible for you to just get a dedicated 65G bolt from AA? At the very, very least (and this is not an "AA-approved" solution ;)), could you get a dedicated 7.62x39 bolt from DPMS?

John

Well I didn't describe the bolt well enough.

This is a bolt action rifle, not an AR. I am left handed and we are on the short end of the stick.

I spoke with Bill before and after the build and the rifle will take the Grendel just fine.

The bolt face is currently .439 and the brass is .440. Very tight fit and the bolt will not close on the brass. I am thinking that the face should be .442 to .445 to make it work properly.

I have emailed Bill for the dimensions and will hear back from him soon I am sure.

I will have to send it off and have the face done again but this time I will not pay for a job that isn't correct.

I just wanted someone with a Grendel to chime in and give me the dimension of their bolt face so that I might have the measurement in hand when I send the action off again for the job to be done right.

Just wait for Bill.

If I talk to him first I will ask him.

Sometimes people can get a dimension on a vernier that is just slightly off.

That can effect accuracy and or function.

Is it a Savage?

If it is get the Scope base from Badger Ordinance

I think he mentioned Charles Daly; I'd guess it's one of their small Mauser actions, which would make a cool Grendel bolt gun.

John

Well I didn't describe the bolt well enough.

This is a bolt action rifle, not an AR. I am left handed and we are on the short end of the stick.

I spoke with Bill before and after the build and the rifle will take the Grendel just fine.

The bolt face is currently .439 and the brass is .440. Very tight fit and the bolt will not close on the brass. I am thinking that the face should be .442 to .445 to make it work properly.

I have emailed Bill for the dimensions and will hear back from him soon I am sure.

I will have to send it off and have the face done again but this time I will not pay for a job that isn't correct.

I just wanted someone with a Grendel to chime in and give me the dimension of their bolt face so that I might have the measurement in hand when I send the action off again for the job to be done right.


Just to be sure the the bolt not closing on a case isn't in fact the case not sized enough for the chamber, turn a little bit of the rim (while trying it in the face of your removed bolt) and then try chambering it. Remember all the AR's that have chambering problems because of the dies not sizing the brass enough. If I remember correctly that Charles Daly was made in 7.62x39 caliber right? The Grendel rim should fit it, but, hey, maybe one got out the factory on the tight side.

Joe

The bolt face measures 0.454" diameter and 0.136" depth

Thanks warped. That is what I figured. The bolt face is the problem. It measures .439, way too small.

They do make it in 7.62 but of course not in left hand.

I now have a plan and will get this thing to shoot or else :)

Thanks for all the help. Perhaps a round will go off in this piece before next year. At the rate I'm going it might be next summer.

What rifle is it?

Maybe we can help.

If needed I am sure someone can make you a bolt. (but it won't be cheap)

Warped the rifle is a Charles Daly left hand mini mauser. I have contacted and spoken with James Anderson and will be sending the action to him for the final word.

After seeing his work on 24hr on the rifle that he has gone over there, another mini mauser I called him and asked that he take care of it. He was most gracious and will check the feeding, open the bolt face, and make sure that all is well.

I don't think that a new bolt is necessary. I would just trash the action as they were not that expensive to start with. I should have made sure of some things before diving head first into a Grendel.

A friend of mine mentioned the Grendel for that action and I went nuts and just had to have one without researching all that it entailed.

Thanks for all your help and perhaps when I finally finish the project I will post a picture or two of the rifle. I had a nice figured Myrtle stock turned and will be putting the final work into the stock while the action is in the works.

Might get to shoot it this year I hope.

Cool, I hope it all works out.

Maybe I missed something here but how did the smith headspace this without the bolt closing?

The bolt would actually close on the gauges. The rim of the gauge is smaller than the actual brass.

There was clearance between the gauge and the bolt face but not the brass.

Ok, got it. Does the case rim fit between the extractor and bolt face? The smith should be able to open up the bolt enough on the lathe for the case to fit/bolt to close.

Head of 6.5 Grendel brass is .4449.

Phil

But if he's using fire formed 7.62x39 brass its slightly larger at 0.447"

Head of 6.5 Grendel brass is .4449.

Phil


I already told him the exact specs of the bolt face, that is per Bill Alexander.

If it fits, it works,.

Ok, got it. Does the case rim fit between the extractor and bolt face? The smith should be able to open up the bolt enough on the lathe for the case to fit/bolt to close.


You remove the extractor initially to test tolerances.

The extractor is set inwards do to spring tension.

As the face is circular and only a small portion is the extractor gap, it is enough of a gauge.

You remove the extractor initially to test tolerances.

The extractor is set inwards do to spring tension.

As the face is circular and only a small portion is the extractor gap, it is enough of a gauge.
His bolt might have been from a 223 with that Mini-mauser. Its got a claw extractor and controlled round feed if the bolt is a true mauser type not like the completely enclosed bolt face of a Rem 700 push feed. if he is using 7.62x39 brass and his bolt was set tight for factory grendel brass then its too tight to use with other types of brass.

It was a 223 to start.

The bolt is not a true Mauser. It doesn't have a claw extractor. It fits into the bolt face much like a Sako or Remington with an extractor.

I finally found a box of Lapua Grendel brass and Bill suggested that I not use the PPU that I purchased used. I have used two mics and my dial caliper and all the brass even the used measures .440. I have some 7.62 on the way but the rifle is off to James Anderson this week.

I feel that the extractor is too thin where the bolt was opened up so I will have him install and fit a new one, open the bolt face, and make sure that it feeds from the magazine.

Been waiting a long time to shoot this thing but will just keep collecting components and get ready when I do get a chance to shoot it.

Is there any accuracy difference in the brass? PPU, Lapua, or the 7.62 Winchester brass. I know that the Lapua is small rifle primer and the other large but is there a better brass?

That makes more sense then. The bolt face is just a little off. Could be under the extractor. If it were mine, I'd have him open it enough to feed a case that is necked from a 7.62x39. You'll be able to use more of a variety of brass. There are many posts here on which is the most accurate,long life cases. I'd say some of it would depend on what you're going to do with the rifle. Some of the members say they have found zero difference in case life or accuracy with necked down, fire-formed 7.62x39 brass vs the factory brass. Its certainly cheaper to use 7.62x39 brass. Being you have a bolt gun and don't have to concern yourself with softer primers and slam fires, you could experiment with large pistol primers vs rifle if you think a regular large rifle primer is too much for the case. I just not convinced the large primer is too much for the majority of shooters. I've got nothing but necked down brass loaded. I'm not shooting bench so I don't need to be that anal with my brass. For most shooters, IMHO, I don't think you would find a difference between the two types of brass to warrant the cost of small primer brass.

It makes much more sense now.

Thanks for the details.

Thanks glane. I am going to do just that. I just don't see why Grendel is twice what I can buy 7.62 Lapua brass.

I don't bench any rifle that I have but I do expect under an inch. I have some Winchester 7.62 brass on the way and will send al three, Lapua, PPU, and Winchester. 7.62 and Grendel.

I will get this rifle to function. I have great expectations for this caliber. I hope that the caliber will be my pig, coyote, bobcat, deer, prairie dog etc.

Well crap perhaps I don't want to finish this rifle. If this caliber is as good as it sounds my other rifles might not see any action and then they might be thought of as just dead weight. NAAW :)

Thanks glane. I am going to do just that. I just don't see why Grendel is twice what I can buy 7.62 Lapua brass.

I don't bench any rifle that I have but I do expect under an inch. I have some Winchester 7.62 brass on the way and will send al three, Lapua, PPU, and Winchester. 7.62 and Grendel.

I will get this rifle to function. I have great expectations for this caliber. I hope that the caliber will be my pig, coyote, bobcat, deer, prairie dog etc.

Well crap perhaps I don't want to finish this rifle. If this caliber is as good as it sounds my other rifles might not see any action and then they might be thought of as just dead weight. NAAW :)

Your welcome. What bbl are you using? Twist? I doubt you have any problems with accuracy. If you have a quality barrel and your smith did his part with chambering and mating to the receiver, it should be a tack driver. I don't recall if you said what stock you were using but make sure it is bedded properly. I pillar/glass bed my bolt guns unless they have the bedding block already in the stock. Make sure your trigger is crisp but safe. I'm only using IMI, Winchester and some Federal 7.62x39 brass. Keep an eye out at Widener's. They are out now but they did have 1K round bags of new IMI 7.62x39 brass for a good price. Good luck with your project and let us know how it shoots/what loads used etc.
Greg