over pressure - sticky chamber /dies / rifle ??

I had an A-bolt in 300 winch that would not accept neck only reloads......then I realized that even just fired cases would not rechamber after they where ejected...so I marked with Sharpy the case at the 12 o'clock and rechambered at the same mark ,even after neck sizing
if I used the 12 o'clock mark it would work.......
oval chambering
 
Well -- I cleaned the chamber as good as I can , looks clean by my eye and this gun is in mint shape everywhere else for sure so I'm doubting ( wishful thinking ?) corrosion . Now I did mark the brass after firing and with the min load shot brass by marking it at different positions it does feel better at a certain position so the chamber seems slightly off round .

So I put the same brass through my Redding body die and spun it about 6 positions stroking the press each time -- and the brass still fits tight !!?
The first 10 brass with heavier bullets and medium loads will not chamber at all .
So --- I'm thinking the first 10 brass were overloaded expanding the base possibly destroying these cases
The other fired brass from the reduced loads reload and fit tight causing extra pressure on the second firing shown by a stiff but workable bolt lift
New brass now fire the light bullets with a medium load (my max )with just a slight stiff bolt lift

So now I need to buy / borrow different dies to see if I can size the brass to match the PPU size
And I'm still going to get it to a bore scope to have a better look
 
Keithjohn said:
Well -- I cleaned the chamber as good as I can , looks clean by my eye and this gun is in mint shape everywhere else for sure so I'm doubting ( wishful thinking ?) corrosion . Now I did mark the brass after firing and with the min load shot brass by marking it at different positions it does feel better at a certain position so the chamber seems slightly off round .

So I put the same brass through my Redding body die and spun it about 6 positions stroking the press each time -- and the brass still fits tight !!?
The first 10 brass with heavier bullets and medium loads will not chamber at all .
So --- I'm thinking the first 10 brass were overloaded expanding the base possibly destroying these cases
The other fired brass from the reduced loads reload and fit tight causing extra pressure on the second firing shown by a stiff but workable bolt lift
New brass now fire the light bullets with a medium load (my max )with just a slight stiff bolt lift

So now I need to buy / borrow different dies to see if I can size the brass to match the PPU size
And I'm still going to get it to a bore scope to have a better look
Click to expand...

sounds like that action has alot of spring under firing pressure allowing the cases to expand way too much. Is this a front or rear locking bolt?

Or the chamber is not round.

The body die may not size the case body so any bulge is not sized down. The test I suggested is for the fired unsized case... did you try that yet?

Is your press shellholder hitting the bottom of the body die BEFORE the press lever gets to the bottom? Try making contact about 2/3 of the way down. Use more lube and see if you can bump the shoulder back as much as possible.

If that still fails, you can try a FL sizing die but I would also look at the lock up of the action.

Jerry
 
It's a rear locking bolt ( 4 lugs ) I don't know what to look for with a lug fault
I did do the test to see if the chamber is round and found it a bit off by bolt feel
 
Keithjohn said:
It's a rear locking bolt ( 4 lugs ) I don't know what to look for with a lug fault
I did do the test to see if the chamber is round and found it a bit off by bolt feel
Click to expand...

So you likely have the worst of all worlds... a springy lock up and an out of round chamber. Any rear locking action can have the front of the bolt move under the pressure of firing. The rear may be fine, but the front can move. Or worst case, it is all moving. Look for even wear on the backs of each bolt lug. Cover with persian blue or jiffy marker and see how it rubs off with cycling.

If you are going to shoot this rifle, consider the lightest bullets with the slowest powders and stick well below max loads from reliable printed data.

You will need to consider FL sizing the brass so that it will go into the chamber and if you keep pressures real low, the case will not expand/bend enough to jam up.

Might be time to retire this gem.

Jerry
 
I've heard of the S&L having a bit springy action due to the rear lugs. I would try using a regular FL die. Start it a little high and screw it in tip it just sizes the brass. Never used a S&L because they were not LH but would try this. I loaded a lot for Rem 788s with a similar setup and never had problems. A lot for the 6mm were Fl dies back off until I was just sizing the neck and these were hot loads >i's successful baking off FL dies in a tapered case like the 6mm or 270 etc. I've only ever had problems doing this with 3 rifles. 2 were Sako 243's and a 325wsm. If the chamber is oversize in a fairly straight wall case the dies will make the case smaller as it enters the die to partially neck size it. When that happens the body lengthens because it is reduced in dia. you have to turn it in the die until it just fl sizes the brass.
 
My issue is now not the brass or dies . My rifle for some reason is showing high pressure ( stiff bolt ) at min loads with light bullets
Looks like I need a Shultz and Larson gunsmith .

Any suggestions ?
 
I can't help about a Shultz and Larson gunsmith, but your comment about "high pressure" reminded me that, although my S&L bolt was hard to lift with start loads of Hornady 154 gr. and IMR 4350, the primers (Federal 210) showed virtually no sign of flattening at the corners. The NORMA factory 160 gr. had the NP marked primers were very flat and much harder to open bolt. Without chronographing, but based on primer appearance, I made the assumption that the start loads were much less pressure, despite displaying the stiff bolt lift, so that led me to investigate chamber and neck finish. An oval chamber (although I have never seen one), would lead to similar symptoms. I never did examine bolt lugs or bolt seats for signs of setback?
 
Potashminer said:
I can't help about a Shultz and Larson gunsmith, but your comment about "high pressure" reminded me that, although my S&L bolt was hard to lift with start loads of Hornady 154 gr. and IMR 4350, the primers (Federal 210) showed virtually no sign of flattening at the corners. The NORMA factory 160 gr. had the NP marked primers were very flat and much harder to open bolt. Without chronographing, but based on primer appearance, I made the assumption that the start loads were much less pressure, despite displaying the stiff bolt lift, so that led me to investigate chamber and neck finish. An oval chamber (although I have never seen one), would lead to similar symptoms. I never did examine bolt lugs or bolt seats for signs of setback?
Click to expand...

My primers look fine too , Is it possible to find out if the laythe work that was done to the gun you talk about involved squaring the bolt or bbl set back ? Or was it just polishing the chamber ?
 
Keithjohn said:
My issue is now not the brass or dies . My rifle for some reason is showing high pressure ( stiff bolt ) at min loads with light bullets
Looks like I need a Shultz and Larson gunsmith .

Any suggestions ?
Click to expand...

When a gun goes bang, the case expands, pressure is put on the bolt head which pushes back on the receiver recess... and if pressures are high enough, other parts of the action and/or barrel also expand. When the pressure subsides, everything goes back to orig and the case springs back to be smaller then the chamber. you can get the case out.

When an action has "spring", the cartridge is allowed to expand too much and even when it springs back, is a super tight fit in the chamber. That is why a "low pressure load" is tough to extract. For this action, the pressure is already moving things too much.

Solutions: light bullet with slow powder (use proper load data) in the toughest cases you can use. Or, powders designed to be run at very low pressures like Trailboss and H4895. Eventually, you will drop pressures low enough that the action doesn't move... the case is supported and doesn't swell... proper operation is allowed.

It is simple but maybe not ideal. Cast bullet loads would eliminate this problem... not sure how you feel about cast bullet shooting but the pressure issues would be gone.

Jerry
 
So , I bought a box of hornady superformance 95gr sst and tried them with apprehension as I'm sure these are loaded hotter than my handloads and to my amazement the bolt lift was much better ( maybe normal for this rifle ) and the fired case went into the chamber with just a little resistance . Once I resized the hornady case it fit in better than any of the low loads in the ppu brass ??? Remember the warm loaded ppu brass would not chamber at all ( case near head expanded ? )

I did clean the chamber with a brass brush but could not see the diff by eye
Ppu vs hornady brass ?
 
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Privi brass is harder and thicker than most brass. If the yield strength is too high, then re-sizing is compromised, particularly at the base of the case. Alternatively, the expander ball can pull excessively on the neck and shoulder during the upstroke, causing the shoulder to deform. I've had both these things happen on resized brass from factory ammo - perhaps they don't both to anneal the brass on factory ammo?
 
UPDATE - I got a set of RCBS full length dies and ran all the ppu brass through and even the ones I thought were over pressured and would not chamber at all fed just fine once full sized !!!

So -- go figure -- now I'm wondering if part or all of the stiff bolt lift is just the nature of the beast with the S&L action

Still confused but starting to get that warm fuzzy feeling about this gun - now back to seeing how it shoots and how the brass fairs
 
I have owned several S&L rifles and have never had a problem with any of them. Yes they have 4 rear locking lugs. They also have a very strong ,heavy walled tubular receiver. Many think that a rear lug action is springy and not strong. The SMLE action has this problem but the S&L action ,the Rem 788 and the Golden Eagle action are not springy actions. They will stand as much pressure as front locking actions. I still have a 7x61 S&L rifle and it is loaded to as high a pressure as anything on the market and I have zero issues. I also have brass that has been loaded 10 + times and still going strong. If an action was springy you would experience case head separation long before 10 firings. Also remember that when Roy Weatherby introduced his 378 Wby cartridge it was originally chambered in the S&L action. I don't think Roy would have choosen a springy action that wasn't strong for the 378 ! The Mk V action was introduced several years after and Wby stopped using the S&L action at that time.
As for PPU brass. I have used it in a number of calibres. Generally speaking it is heavier brass with less case capacity than Win, Rem , Fed cases. Max loads will be 2 or 3 grs LESS in PPU cases than in other brands of cases. Case dimensions seem to be slightly larger or "fuller" than most north American brass. I have a BSA CF 2 rifle in 7.5x55 Swiss and new PPU cases will NOT chamber in that rifle. I run them through my FL size die and they fit snugly. Once fire-formed they extract and chamber slicker than owl ####.
I think your rifle is chambered to minimum sized specs and your first set of dies were made slightly larger. Your new dies seem to have cured your problem. One suggestion is to lube the inside of the case necks when re-sizing. This will prevent the expander from distorting the case necks and making the cases hard to chamber. I use powdered graphite applied with a Q-tip. Works good and zero clean up required.
 
Thanks rokoro, I think I am good , I hope , what do you have to say about the bolt lift on S&L rifles compared to front lug rifles ?
It now seems the only pressure sign I see is the bolt lift
 
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