8x57 k98

[pupsdad]

I'm actually putting quite a bit of effort into my K 98 project in the hope that an 8x57 will be a better than average cast bullet rifle. I like the case size an 8mm is almost a 35 but my barrel is an old military one that slugged OK, it is going to need to have chamber cut deeper so I'll have a new throat. I guess it will be keep my fingers crossed and hope the barrel will shoot.

[Scharfschuetze]

Good luck with your Mauser project. They really are great rifles and the 8X57 Mauser is a very good cartridge.

Why do you need to cut the chamber deeper? Also, Mauser throats are very long in comparison to most other military rifles.

Is this the same rifle that you have another thread on?

http://castboolits.gunloads.com/show...3-K-98-project

[pupsdad]

Head space is off.

[waksupi]

Can you load the bullet out further?

[Scharfschuetze]

If your K98 is a German made Mauser with an original barrel, the headspace is no doubt within manufacturers tolerances unless it's a very late WWII build. Can you elucidate on why you suspect this? Perhaps the issue is elsewhere.

[LAGS]

If you cut the throat deeper, you are increasing the headspace, unless you have the barrel set back.
But in a lot of cases, you can ream it or have it reamed out to 8mm-06 and cure both issues
That is the original Poor Mans Magnum.

[Multigunner]

If headspace is really off you'd best check the inside of the receiver ring for signs of setback. Not much sense in building a custom rifle on this action unless you can correct any setback first.
The equipment for doing this is available from Brownells. A friend used to do this with his own homemade setup made from a barrel stub bored out for an arbor to which he mounted a diamond cutting wheel.
He called this process blueprinting and it worked so well he used this method on all the actions he worked on when building long range target rifles. Apparently it greatly improved group sizes of most rifles.
To do this the barrel must be removed, so correcting any headspace problems can be done at the same time. Mauser military sights are soldered on , no key slots cut in the barrel, so remounting the sights is no biggie.

Remington marketed an 8mm magnum cartridge, haven't heard much about it. Perhaps a conversion to this cartridge would be better than the 8mm-06. Bolt face would have to be opened up though.
With the 8mm-06 there would be no end of once fired cases available for necking up, which was the main reason for this conversion back in the day.

[pupsdad]

This rifle is being put together from parts action, barrel, stock. It has been set back so it needs the head space set. This will be cast only so
It will stay 8x57.

[Scharfschuetze]

If you don't plan to shoot factory ammo through the rifle, you could always just remove the required amount from the bottom of your dies to size to your chamber. That will achieve your head space goals without too much effort. The only extra effort with the bras will be to trim it by the amount your remove from your dies. I guess that would be the measurement of how many threads the barrel was set back by.

In addition, a shorter case will reduce your powder capacity somewhat which is usually good for a cast boolit cartridge's ballistic uniformity. Of course you'll end up with a rifle only you can load for, but then you could call it your own Wildcat round.

[Multigunner]

So Pupsdad are you saying the headspace is too tight as is, the bolt not closing on a round?
I had thought you meant the headspace was too loose.

If too tight Brownells also has "Breeching Washers" ultra thin hardened washers you put under the breech of the barrel to achieve proper headspace. I remember they had these for the small ring mausers, not sure if they have them for the 98. IIRC the ones for the mauser are C shaped.

[pupsdad]

Yep will not close on a round. I'm kind of leaning towards renting a reamer it's a used barrel and that would give me a fresh throat.

[pupsdad]

Yes this is the same rifle in the other thread I was wanting to talk about the 8x57 and how it ranks in cast bullet shooting. I should have been more clear.

[Ben]

LAGS,

If you cut the throat deeper, you are increasing the headspace ? ?

Am I missing something here ?
The cartridge does not head space off the throat.

Ben

[LAGS]

Unless you have a reamer that Only Cuts the Throat, the sholder will be cut deeper too, thus increasing the headspace.
But if he has a Short chamber condition, then reaming the chamber is the right way to do it.
It will cut the headspace and the throat depth to the proper length.
The way he was talking, it sounded like he wanted to deepen the throat to shoot cast Boolits on a rifle with too much headspace.
Just rent a chamber reamer in 8x57 and an extension T handle, and the Go and No- Go Gages and the chamber can be headspaced in a matter of minutes.
I set my barrels to a light drag on the Go Gage. But, I dont hunt dangerous game here in Arizona.
And I would not have any issues with shooting Factory ammo in a Mauser that has had the barrel set back less then three threads.
Now if you wanted to rechamber it to 8mm Magnum, then dont use a set back barrel.
I have had to set back many of my Mausers one or two threads, and never have had an issue.
But they were set back because they came with a Mis Matched Bolt, or some Yahoo tried to lap the lugs with out setting the barrel back first. Thus, they increased the headspace.

[Ben]

OK, that makes sense !
Thanks,
Ben

[pupsdad]

Thank you Lags good explanation I do have trouble getting my thoughts out but I hope every one understands were I'm going now.

[Doc1]

I have worked with a lot of 98s and never saw one in factory trim where the bolt wouldn't close (headspace too tight) with in-spec ammunition. If this is a parts gun without matching numbers and no collector value, the first thing I'd do is swap bolts with one or two other rifles/bolts. 98 bolts are still pretty cheap and 98s are one of the world's easiest rifles to change and fit bolts for. I've fixed a couple of headspace issues by merely swapping bolts. Easy-peasy. I'm not suggesting that you be sloppy with your headspace, but the basic 98 action is extremely strong and countless examples have been rechambered for 60,000 PSI+ magnum cartridges. The relatively modest pressures of cast loads presents no challenges to this venerable old war horse. Also, FWIW, 98s in 7.92x57 tend to make excellent cast shooters if the bores are in decent condition.

Best regards
Doc

[LAGS]

I agree with Doc1
The 8x57 is a great Cast Shooter.
I have 27 Mausers, and most are still in the 8x57.
They like heavy Boolits, and do well with powder coated Boolits.
Even with Fair but smooth bores, ( Frosted or oversized ) they shoot well out to 200 yards.
Swapping the bolt is a good idea, especially if you are shooting Cast loads at Cast Load Pressures.
But if you are shooting Full Bore J loads, I would set the headspace correctly, or at least make sure that you are gettin good bolt Lug contact on Both front lugs.
Swapping bolts can get the headspace closer or even correct.
But if Both front lugs are not contacting the receiver , or not equally, your accuracy or pressure limits might be compromised.
You can check your bolt lug contact easily with a Felt Tipped Pen.