I have an 8mm Mauser in a standard length action. What is involved in Lengthing the throat on this rifle to allow seating bullets farther out of the brass? There is plenty of magazine length to accommodate a longer cartridge. Would the barrel have to be removed to do this?

Nope; all you need is a throater, available from all the reamer makers for $50 to 55. . You can use a T handle through your action to cut your throat as long as you want it. They are piloted like a reamer.

You can also rent a throater. Much more cost effective for a onesie.

Just google reamer rentals.

Much of this type of discussion talks of throat length but throat diameter is rarely mentioned ! Over diameter will let the bullet wobble !

An 8mm throater would be made the correct diameter wouldn't ya' think?

Now you would need to make sure what size bore you had, what is it on 8mm old .318 and new .323?????

Yes, Manson, Clymer and PTG all know how big to make the throaters; same as their chamber reamer throats are. usually about half to one thousandth over bullet dia.

Thanks. My rifle is the 8x57js (323). I think I can do this.

I would not do that. Once it is done factory ammo won't work as well, it will be a little slower and less accurate. You will not gain any signifiacn velocity with your handloads and it won't likley shoot any more accurately. You are creating a sort of wildcat. It is a make work project in my opinion. The Mauser boys probably knew what they were doing in the first place.

Duckhunter, it's an easy job. Just dip the reamer in good cutting oil and go very slow. The job will take about 10 minutes including cleanup.
In a bolt rifle, you may need the reamer extension...grab a T-handle to turn the reamer.
https://4drentals.com/product/8mm-throater/
https://4drentals.com/product/...le-reamer-extension/

Duck,

I'll ask, just to be sure. Do you know how to measure your progress if you lengthen the throat?

Make a dummy round the length of the magazine, or the length you want, with the bullet you want to use. Keep in mind different bullets relate to the throat length differently based on the ogive used in their design. Round nose contact before spitzers and both before a VLD.

Take the bolt apart so there is no extractor (Mauser), or collar and remove the cocking piece/shroud/firing pin. If not a Mauser, remove the ejector from the bolt. You don't want any resistance to the bolt sliding into the action.

Oil the reamer and ream a little, like 2-3 turns with light pressure on the reamer. It will cut on its own without having to shove on it. You'll feel the flutes cut the rifling.

Clean the barrel of chips. Insert the dummy round and gently push it in. It should contact the rifling prior to the bolt closing. Be gentle here, you don't want to change the length of the dummy round, and you don't want to jam the bullet into the rifling where it could stick and stay.

Ream a little more, go slow. A couple turns, then check again. Take your time here. Better to take an hour than to take a minute, and say oh shit. Eventually, the bolt will just close on the dummy round. At that point the COAL and throat match for the max length of the magazine or COAL that you chose.

Some want the ability to load the bullet touching or even into the lands. For a hunting rifle, I think you need a minimum of 0.005" of clearance so you don't ever stick a bullet. If you use the max magazine length, you are good since the cartridge has to be slightly short to even feed out of the magazine. Otherwise, go 0.010" shorter than mag length for a touching the lands possible fit.

Jeremy

Do you have a military barrel or a commercial one? The military barrels were throated 3 calibers.

Three calibers would give you a .960 long throat. I don't think they are that long.
Scott; he wants to hand load bullets far out; so for the OP it might work well to gain powder space.

I dunno Tom. Back in the day I had a couple of those military 8mm rifles and I used to buy that surplus, cupronickel fodder left over from god knows what war that had bullets-A-hangin out of them so far they came with training wheels to keep them from drooping. I always thought that maybe the Krauts were invoking shenanigans to keep their soldiers from shooting so much ammo. But the damned stuff always went into the guns I had and went boom. It was before my gun-plumbing days, but some of those bullets had to have been seated out a full inch or more. They were hung like Bull Gerbils !

True; I have a hundred 8mm barrels but not with me right at the moment. They do have long throats but I guess I never measured one. Personal failure, I know. They probably are 3 calibers; Bobster is never wrong, unlike me. Maybe you.

Hell Tom. I've never been wrong! Fearsome confused well past the point of catastrophic failure and disaster MANY TIMES, but never wrong !

I was going to post the "lengthen the throat on a 8x57?" question Walt on but I backed away from the keyboard carefully...

I agree with the process as outlined by farbedo with one addition. I add a collar to the throat reamer, the diameter of the bolt and attached to the reamer with a set screw. I set the collar so that it will only allow a small cut before contacting the back of the barrel. I make that cut. I then place a sized brass into the chamber and measure the distance from the head of the brass to the back of the receiver. Then I place the brass with the bullet loaded to the required length (as outlined by Farbedo) in the chamber and measure from the head to the same position on the back of the receiver. I subtract the shorter measurement from the longer and move the collar to the rear of the reamer that amount and lock it down. I then make my cut until the collar contacts the back of the barrel, and I got it! I do not have to depend on feel to get it exact. The collar controls the depth of the cut and holds the rear end of the reamer in alignment with the bore.

The small collar goes down the bolt raceway. The large is for when the barrel is off the action. I have since made a small collar which is 2 inches long for short cartridges. It will extend over the reamer.

Reamer extension by Rod Henrickson, on Flickr

Hell I was wrong. Just re-checked Olson 3rd Edition P.104,3rd para. "In addition to possessing deep grooves, Mauser 98 barrels made to fire the "S" cartridge had an unusually long forcing cone (about 4 1/2 calibers) which extended in a straight taper from the forward end of the chamber to the top of the lands"

quote:

Originally posted by dpcd:
Three calibers would give you a .960 long throat. I don't think they are that long.
Scott; he wants to hand load bullets far out; so for the OP it might work well to gain powder space.

Well, that doesn't quite equate to a 1.4 inch throat. But you could still jam one hell of a long bullet into it with very little resistance. Depending on the bore diameter, I can see where the Germans would want to use a long lead to get the pressures down with deep grooves and long bullets.

I was quietly wishing that I had taken some pictures of those long bullets I used to buy as a kid. The old timers in my area used to call them steel/jacks or armor piercing. They used to claim that you could shoot through a tractor end for end with them. Later in life I learned that it was all BS and that they were actually a copper/nickel alloy and not steel at all. Besides that, it was a farm/ranch community and shooting innocent tractors was a hangin offense so I know for a fact the theory was never tested. Oddly enough when I googled the description, hundreds of pictures of those long nosed buggers popped up. So I wasn't lying. Nutz yes, but not a fibber!

Ammo-german-02-military by Rod Henrickson, on Flickr

Thanks for this post and lively discussion. I have a Krieger AR barrel in .223 that I want throated to .223 Wylde. I will have that done soon.

Thanks for all the information, but where was the invective and name calling. Are we all growing polite in our golden years?

quote:

Originally posted by lawndart:
Thanks for all the information, but where was the invective and name calling. Are we all growing polite in our golden years?

Tom was too tired.

I was too lazy.

Bobster searched Olsens book but could not find a colorful noun or metaphor.

Fury01 was to cautious.

mete tried to lead everyone off on a tangent.

farbedo went off on a tangent and didn't realize there was a fight.

A couple other guys had the audacity to answer the question.

The forum is basically going to hell in a handcart ! LOL