Hello Guys

I have two Mauser sporters in 250-3000, a very original rifle manufactured in 1931 and one with no bolt, manufactured 1923.

So I have been interested in using the bolt from one rifle in the other (these are kurz actions so the bolts are as rare as rocking horse poop). I finally got both rifles and some cartridges together to see what I had. At the only local smith who has headspace gauges for 250-3000, both rifles take both the Go and No-Go gauges ! He doesn’t have a field gauge and avowed that he’d be happy to shoot the rifle with numbered bolt – I have to say that I remained unconvinced following this discussion.

I had to hand:

­Winchester Factory Ammo

­“Reloads A” – Winchester brass resized using RCBS Full length dies

­“Reloads B” – various brass resized using unknown dies but looks like it has been full length resized.


Both rifles chamber the Winchester Factory ammo
Both rifles will just chamber Reloads A – there is some resistance
Neither rifle will chamber Reloads B

Both rifles will just chamber Winchester Factory ammo with 3 layers of masking tape on the base, which I measure at .009” in total - horrors because I thought maximum headspace should only be .006"

All the tests were carried out with the firing pin and its mechanism removed but extractor in place.

Anyone able to offer an explanation of what is going on here? Is either rifle safe to shoot as is ?

Thanks - Foster

You have 2 old rifles. Who knows what gauges were used back then. Get a tool capable of measuring from the datum ring on the shoulder to the head of a cartridge case.

Take a similar cartridge case with a longer shoulder such as a .243 and trim under length a little. Push the shoulder back until it will chamber with a tiny bit of drag when the bolt closes. Measure that case from datum ring to head. That is the actual dimension of your chamber.

You can compare that number:

Between the two rifles
Between the rifles and FL dies all the way down
Between rifles and factory ammo.

Such a tool is marketed by Hornady (the old Stoney Point tool) or you can have a smith make you one.

An advanced handloader may have better tools at hand to do this than your average gunsmith.

"Excessive" headspace is addressed by building ammunition which fits the chamber, and that's not rocket science. There are a couple of ways of doing that:

1. Simply seat the bullet out far enough to engage the lands (using a fairly mild powder charge to ensure this doesn't cause excessive pressures). This will hold the case firmly against the bolt face, thus when fired the expansion of the case will be mostly forward and the fired case will fit the chamber without stretching in the critical web area.

2. Take any larger case on the same head (.243 would work nicely) and after trimming it to the proper length for the .250 Savage run it into your Savage FL die, but only so far as to allow it to chamber with some resistance as you turn down the bolt handle. The forward-located shoulder will hold the case against the bolt face, and as in instance #1 will provide you a perfectly formed case upon firing (in this instance you need not reduce your load from a full-power charge.)

The second method is somewhat better in my opinion, but either will work. From this point on, screw your die into the press only so far as necessary to allow resized brass to chamber without excessive resistance. Sizine them down further will recreate the "headspace" situtation you've just solved. Keep brass properly separated for each rifle as neither will have exactly the same headspace nor chamber dimensions.

If it were me I would shoot a round or two of factory ammo in each and inspect the cases. You'll probably get some flattened top hat primers but the cases should now fit your chamber and be ready to reload. Adjust your thinking accordinly to what you see. roger .

Headspace is whatever SAAMI say's it is and there is a tolerance associated with it...something like, but not necessarily exactly, 0.000" - 0.008" or something close...check out the specifics for the 250-3000.

That being said...headspace can be anything within a minus something to as much as 0.025"...

Stonecreek's second method is what I've been using for umpteen years PLUS...after I find the "snug fit" for the case I ALSO seat the bullet out into the lands maybe 0.025" or to where the lands push the bullet back into the case.

Using this method I KNOW that the case will be tight against the bolthead and the firing pin strike WON'T move the case forward.

Use a heavy end bullet weight and a beginning load of the powder that gives the highest velocity at the lowest pressure...get that from a Hodgdon reloading manual.

Pick up a set of Hornady headspace guages for ~$35 bucks...fire off a couple rounds, measure with the headspace gauge...size ONE fired case in your sizing dies screwed down to touch the shell holder then another full turn to take out ALL slop in the press linkage.

Measure the fired and sized case, compare it with the fired case and the difference is the ACTUAL headspace between your sizing die and the chamber.

THEN...buy a Redding Competition shell holder that will size roughly 0.002" LESS than the sized case...lock the sizing die rings and use that comp shell holder from then on.

Do the procedure for BOTH rifles and if there is a large amount of variation is headspace just use a different Comp shell holder to adjust for it.

Alternatively you can make a guage out of just about metal, drill a 11/32" hole in it and use that as a guage...I make guages out of 1" x 1" round/square/hex...brass/alum/steel etc.

From your description I would use the RCBS dies, forget the oddball dies, buy some new brass or buy new factory ammo.

You might also want to find where the bullets touch the lands...AND have your smith make a chamber cast to see just what the neck diameter is...you might be getting resistance due to a smaller than "normal" neck diameter.

As far a swapping the bolt the above procedure will work also...USE THE SHELL HOLDERS to adjust for the headspace...you can also grind off the bottom of the sizing die if the die WON'T push the shoulder back far enough

FORGET ABOUT USING LOADED AMMO when doing this...when I do this procedure with a "new" gun I ALWAYS use NEW BRASS...this will stop a lot of problems before they BECOME problems.

Do a search for "headspace", "bullet to land measuring", neck turning, etc...there is tons of information on those subjects all over this forum.

LUCK

I will get the headspace gauges, thats a no brainer. I still have a question, how come my RCBS dies are not sizing cases enough to fit ? I should point out that these cases have been fired previously in another rifle. Would a Redding comp shellholder maybe fix this. Is it my press ( a Lyman "T-mag" I think, its the one with a rotating head) ?

Thanks

Are you making firm contact with the bottom of the die with the shell holder?

A given FL die may or may not reduce a case fired in another chamber sufficiently for it to fit in your gun's chamber.

Depending on where the dimensional mismatch is located, it may or may not help to run the case further into the die. "More" sizing can be accomplished by either shortening your die at the mouth to allow the case to enter further, or preferably, thinning the lips of the much less expensive (and softer) shell holder. By simply grinding a fraction (.01-.015") off of the top surface of the shell holder, you can effectively push the case further into the die.

If the problem is that the chamber of the gun you are attempting to match has a slightly greater taper at the shoulder than the die, then this might address your problem. However, the wise thing to do is to use a candle to smoke a non-fitting case from the web forward, insert it as far as possible into the chamber, and thus discover where the dimensions are mismatched.

Ultimately, if your chamber is tighter (not necessarily shorter) than most, you may have to search for a die that is also tighter than most.

I have a 264 that would chamber factory ammo but not any reloads, using three different sets of dies (pacific, herters and brand new rcbs). turned out it had a tight neck in the chamber. I was told that factory ammo is often even below min. specs to insure it will chamber and work in every rifle out there.

Red

Custom reamers and dies all have a range of tolerances designated by SAAMI but grinding a reamer in the old days was an art and depended on the tool maker as to what HE thought was the correct way...

Many times the reamer was ground at or slightly over SAAMI max dimensions so they could get more resharpens or "touch-ups" out of the reamer before it was reground to a smaller chamber dimension...all it takes is something to go amiss and those tolerances stack the wrong way. Old timey custom chambers are well known for being somewhat "out of kilter".

Not to diss RCBS, I have a ton of them, but I've had several sizers over the years that wouldn't resize cases to fit the chamber...all it takes is to have a minimum chamber and a maximum sizer die...it's NO ONE'S fault, just the toss of the dice.

I have 3, 4 and 5 different brands of die sets or sizers for a few calibers...Lyman, Lee, RCBS, Redding, Hornady and every one of the sizers will size a different set of measurements... I just use the one that sizes the case to fit the chamber the closest...or in MANY cases I just polish the sizer to fit the chamber.

It ain't no thang...just like knowing a rattlers bite will cause you great difficulty, but you don't necesarily need to know how the chemical process of the neurotoxin.

Again...have a chamber cast done or fire off 3 rounds and send them to a die maker...he will do the measurements and make you a sizer that will WORK.

Stonecreek gave you some good ways to find out what's happening...do them them tell us what happened...maybe someone had the same problems and has a solution.

Did you take all the slop out of the ram like I said?

ANY breakover at the top of the stroke means the press has flexed and the case WASN'T sized to the maximum extent...and I guarantee trying to size the solid section at the bottom of the brass case is TOUGH.

I think your problems can be solved relatively easily, but you need to give some definitive and specific measurements for a case fired in EACH rifle by swapping the bolt around.

Using a Hornady headspace guage may be a no-brainer, but as far as I've seen, there are a lot of no-brained individuals out there who refuse to use them and still whine about "problems" with their shooters.

The Redding Comp Shell holder is to correct base to shoulder measurements, but will slightly change the case taper measurements as will grinding off the bottom of the die or the top of a standard shell holder...I have done both at times...

I like to do the die though because then I can use Comp shell holders to adjust in 0.002" increments...this is only needed in benchrest/target/highly accurate varminters... BUT I wouldn't grind off more than 0.005" at a time.

Basically it depends on what metalworking capacities you have available as to which is the quickest and easiest way to accomplish your solution.

Or use it like it is. Work up an accurate load and call it good...it depends on YOUR accuracy requirements, and a snug chamber isn't all that bad anyway unless it interfers with your level of accuracy...I like a nice snug chamber depending on WHERE the snuggness is.

LUCK

There are a couple of comments on the advise given.

Stonecreek
one of us
Posted 28 March 2011 19:49 Hide Post
"Excessive" headspace is addressed by building ammunition which fits the chamber, and that's not rocket science. There are a couple of ways of doing that:



2. Take any larger case on the same head (.243 would work nicely) and after trimming it to the proper length for the .250 Savage run it into your Savage FL die, but only so far as to allow it to chamber with some resistance as you turn down the bolt handle.


I would measure the difference between the base to shoulder length of the factory ammo and those from handload A. I would also de-bullet a case from handload A to make sure it was the case that was giving the 'feel'and not the bullet contacting the lands. This will tell you whether factory ammo is within spec for your chamber.


Tentman
one of us
Posted 29 March 2011 11:49 Hide Post
I will get the headspace gauges, thats a no brainer. I still have a question, how come my RCBS dies are not sizing cases enough to fit ? I should point out that these cases have been fired previously in another rifle. Would a Redding comp shellholder maybe fix this. Is it my press ( a Lyman "T-mag" I think, its the one with a rotating head) ?


The simplest "fix"for this is to dress a shell holder and try a case. Dress the shell holder rather than the die. Dress and try till you get feel with the die set on the shell holder, then take a further 1 to 2 thou. It is not uncommon for shell holders and dies to bet at opposite ends of the min-max dimensions and is the reason for the Redding competition shell holders. I have a couple of shell holders I have dressed down to get a custom fit to one of my chambers. I swapped shell holders with a friend for his 338LM because we set his dies with my shell holder hard on his die while his shell holder was a couple thou taller.

Von Gruff.

Hello Guys

Thanks forall the info and ideas. The headspace gauges are ordered and I have dressed down a shell holder until cases will chamber. They now "just go" in one rifle and "with resistance" in the other so I'll leave it there and go shooting this weekend.

Thanks again

Foster

Tentman-
You can get better sizing out of a die by double stroking it. Pull the case out of the die just enough to allow you to spin it 1/2 turn and resize a second time slowly with a dwell at full stroke. This will push the brass back another .002 or so and make the shoulder location much more consistent.

I have a Savage 99 250 with a large chamber, to get better case life I use new cases and bump them up to 7MM on the neck only. Then adjust die till the rifle just closes with resitance. Then load & fireform it. Cases seem to last much longer as brass stretch is even. Important to set die to chamber size after fireforming.