Reloads wont chamber, Swiss K31

[leonard]

If you have a fired case that has not been resized try chambering that case for ease of chambering. If it chambers easier than your resized case it could mean your die is not pushing the shoulder back far enough.

Below you can see the case gets "longer" as it is full length resized and squeezes the shoulder forward. And sometimes when the die is making hard contact with the shell holder with press camover the shoulder is still not pushed back far enough. When this happens you will need to lap the top of the shell holder a few thousandths at a time until the case chambers.

Chambers and dies vary in size and "sometimes" your die does not match your chamber and the case ends up too long after sizing. And then you decrease the hight of the shell holder to push the case further into the die. There is also the possibility the case diameter after sizing is too large, "BUT" most of these chambering problems are cause by the case shoulder not being pushed back far enough.

NOTE, normally when the die matches chamber size the die will push the shoulder back more than needed, and why having the gauge below is good to have.

This is where having a vernier caliper and a Hornady cartridge case headspzes gauge is good to have to measure your unfired, fired and resized cases.

Below measuring a "fired" .223/5.56 case and then setting the die for .003 shoulder bump for my AR15 rifle. Meaning the resized case is .003 shorter than its fired length.

The older method without gauges was to color the case with a black felt tip marker and see where the color has been rubbed off in chambering.

I was going to say similar if you resized the case improperly it will end up with a long neck but the neck will be low. but ends up longer.

Trimming brass every time is needed. i've over resized before when i was inexperienced with reloading thankfully the casing necks ended up dented and i caught onto it early.

Id personally see if a resized brass without anything chambered closed in the rifle.

if it does then you only have a OAL issue perhaps unknown. but if the cartridge can close properly when chambered then the rest is due to OAL

 

[Donkin]

It is the brand of dies that you are using, I had the exact problem when I first started loading for a K31 , was using Lee dies. Switched to Redding dies, problem solved.

 

[LeeEnfieldNo.4_mk1]

What C.O.L are you using and which bullets?

I am using Berger 175g VLD match and I measured the lenth from the Igive of a GP-11 round and set the bullet to match.

I also just tried to chamber two resized cases, neither would chamber. so not a OAL issue. measured them and they came out at 2.182 and 2.196

my set up is using a Hornady LnL Progressive press with Hornady dies.

 

[OldNewGuy]

The first place I would check would be your crimp.
Too much crimp will do that.

Boolitcaster may be spot on here, to add to the mix....I had the same issue with my BLR in .308. Full length resize with "standard" RCBS dies, "lightly" crimped per RCBS instructions, tight chambering or won't chamber. Had suggestions to try a small base die, since the same problem had occurred with to some others with the BLR, although in different calibers. Bought the small base, "lightly" crimped per RCBS instructions - nope, won't chamber well, although very slightly better than the standard dies. Finally, a friend with more experience than I (I've only been reloading since 1978) told me "get the Lee Factory Crimp Die, it's almost certain that the crimp from the full length dies is warping/buckling the brass at the mouth.

I bought it, and every round now chambers perfectly. I ended up buying a Lee FCD for every caliber I own, since I like to put at least a slight crimp on the cartridge to lock in the bullet and make the pressure build up more consistent (not just relying on the friction from the bullet OD to the case mouth ID, which can vary depending on the brass used). And, of course, on my tube mag lever action rifles (Marlin 444S and Winchester Big Bore 94AE) there needs to be a pretty sturdy case crimp to make sure that the projectiles don't get pressed too far into the case with the recoil. I can now use my "standard" RCBS F/L dies no problem.

O.N.G.

 

[LeeEnfieldNo.4_mk1]

Just looked at hornadys website, they have two dies maked for "7.5 Swiss". One if marked "7.5 Swiss K31" (which I bought) the other is marked "7.5 swiss (7.5x55)". I wonder if I have the wrong dies?

 

[diopter]

The 7.5x55 dies can be used for all (including K31) Swiss rifles from the M1889 using GP90 (1890) up to the Stgw57 using GP11 (1911)
The K31 dies are only for the K31.

Depending on the rifles it was shot in, I might have to rotate a case three or 4 times during resizing.
I only use the 7.5x55 dies and use castor oil as case lube. Rifles 1889, 96/11, K11 and multiple K31s

 

[mondostud]

.
K31s all have short throat and therefore require pointy bullets seated deep in the case.

I've reloaded a lot of GP11. This is the correct answer.

 

[LeeEnfieldNo.4_mk1]

OK, So picked up a 7.5x55 Hornady size die, (not the K31 die), ran 2 cases through, tried cambering empty sized case and its still not working. If anything, its actually worse.

All the brass ive tried is within length limits (measured one at 2.188, barly but still within limits of 2.189), Since an empty case wont even fit I doubt its bullet length, Ive tried two different dies, so unless Hornady dies itself are out of limits I have no clue whats going on.

Not the rifle that's for sure, wont work in my K11 either.

 

[diopter]

Are you setting up the dies so they "cam over"? Tight against the shell holder, lower ram, add another 1/8 turn in the die.

 

[LeeEnfieldNo.4_mk1]

Yep, just checked, die to the plate, turn about 1/8. Still the same problem.

 

[gewehr76]

OK, So picked up a 7.5x55 Hornady size die, (not the K31 die), ran 2 cases through, tried cambering empty sized case and its still not working. If anything, its actually worse.

All the brass ive tried is within length limits (measured one at 2.188, barly but still within limits of 2.189), Since an empty case wont even fit I doubt its bullet length, Ive tried two different dies, so unless Hornady dies itself are out of limits I have no clue whats going on.

Not the rifle that's for sure, wont work in my K11 either.

If you can't chamber empty case its either too long or mouth is flared too much. Trim your brass to minimal allowed length.
GP11 has also square shoulder. if your brass is not square shouldered close to GP11 look It won't chamber in K11 or if too low won't chamber in K31. You have to play with your dies. Check your expander is it bottoming on the case webbing? It may be set too low and not allowing your brass to come up to full length of the die and therefore not bumping up the shoulder of the case.

 

[diopter]

Might have a point about the expander. Since you are using GP11 Berdan Primed brass, you can't use the expander rod to deprime. but may need to use it to stretch the neck out again.

 

[LeeEnfieldNo.4_mk1]

Tried again with the ball pulled up but still expands, no way its bottoming out. The decapping pin has been removed but the ball is still there.I think it is the neck, compared to a un-fired GP-11 round and the neck on the round looked a lot shorter but it might just be the lighting.

Last case I tried I painted the neck with a sharpie, there was a faint ring around the neck when I ejected the case.

Kinda confused here. What AM I doing wrong? I am using a Progressive, could there be enough flex in the plate to case the die to not bottom out correctly?

 

[Mystic Precision]

Yep, just checked, die to the plate, turn about 1/8. Still the same problem.

Consider turning the sizing die in a bunch so that the press bottoms on the die about 2/3's of the throw. This is merely a test to see if it is the press flex stopping the sizing from happening

Consider the RCBS liq lube that comes in a 2oz bottle. Apply generously on the case body but not on the shoulder.

Size the case, turn 90deg, size again. If you can measure the headspace, you will be able to track your progress. Hopefully, this solves the empty case chambering problem. If it does not, measure a case that will chamber vs your case. Measure headspace length, shoulder diameter and case body diameter in a few places.

When you say the case doesn't chamber, how far into the chambering process before it stops?

You may have a very short headspace and need to take some off the bottom of your sizer... but try and above first.

Jerry

 

[LeeEnfieldNo.4_mk1]

Consider turning the sizing die in a bunch so that the press bottoms on the die about 2/3's of the throw. This is merely a test to see if it is the press flex stopping the sizing from happening

Consider the RCBS liq lube that comes in a 2oz bottle. Apply generously on the case body but not on the shoulder.

Size the case, turn 90deg, size again. If you can measure the headspace, you will be able to track your progress. Hopefully, this solves the empty case chambering problem. If it does not, measure a case that will chamber vs your case. Measure headspace length, shoulder diameter and case body diameter in a few places.

When you say the case doesn't chamber, how far into the chambering process before it stops?

You may have a very short headspace and need to take some off the bottom of your sizer... but try and above first.

Jerry

It will chamber untill the bolt has almost cammed into battery. The Op rod will be sticking out about 1/8 inch and the bolt only has a few more degrees to go before it is locked. If that makes sense.

 

[diopter]

Since you using the LNL AP Progressive, I wonder if your shell plate might have too much flex or wobble. Try tightening the nut a bit more or insert a hard spacer under the shell plate at the resizing position. Do you have a single stage press lying around you can use just for the resizing operation?

https://www.canadiangunnutz.com/forum/showthread.php/848736-Show-your-reloading-benches/page61

Post 606

 

[Mystic Precision]

It will chamber untill the bolt has almost cammed into battery. The Op rod will be sticking out about 1/8 inch and the bolt only has a few more degrees to go before it is locked. If that makes sense.

Sounds like a combination of problems... press flex, chamber right on min spec, dies just a bit more then min spec.... maybe even inadequate lube.

Easiest way to find the problem is to get your dies into a single stage press... do as I have suggested and prove that the dies WILL size enough.... or not. If not, then you will need to take a bit off the bottom of the die so that you can bump the shoulder more.

Once you have confirmed that the die will size enough, then you can figure out the best way to size the cases.

Personally, I do all my semi brass sizing in a single stage press and then move to the progressive for final steps that do not demand alot of force.

What you have described is a headspace length that is a smidge too long vs the rifle.... and I am thinking the press is the root cause of the problem.

The procedure will identify where your problem lies.... Good luck.

Jerry

 

[gewehr76]

Progressive press may be the issue, or scrap surplus brass and buy proper boxer brass from ppu. Surplus brass is hard to reload as it is by itself let alone on single stage.

 

[LeeEnfieldNo.4_mk1]

Screwed Both dies as far as they will go, sized two in each die, managed to get three of four to chamber, one was normal but the other two needed a bump.

I'm thinking it is the press, so will keep an eye out for a single stage for a good price. With WSS going under I might be able to get one for a bit off.

Also think I need better lube, using the aerosol Hornady stuff and was quite a chore to reize with the 7.5x55 die.

 

[diopter]

Progressive press may be the issue, or scrap surplus brass and buy proper boxer brass from ppu. Surplus brass is hard to reload as it is by itself let alone on single stage.

GP11 brass is wonderful to work with, even though it's Berdan primed. Much easier to F/L size than my first bag of Prvi Brass, which I had to anneal.