Yes, primers backing out can also be an indicator of excessive headspace. I've had this indicator in the past with two rifles. I'd check that first.

eb

You can try that, or you can try another bolt. They're easy enough to find. The problem though is that you can buy another bolt and still be where your at now. The bulge you mention indicates to me an oversize chamber. While not really a problem for a military rifle where reloading isn't an issue, it seems to me that you might look for someone with a chamber reamer and gauges so you can have the barrel set back a thread.

Darn it, where's Riceone when you need him?

You might PM him.

eb

how some of us seem to think that "their advice" is the "best advice," and the only advice worth following. This is generally apparent in their language and low key refutation of a previous post. Some just flat out say somebody else's advice is "wrong."

I'll admit I'm not above arguing a point, or offering counter opinion ,yet I don't think I've ever flat out said another's advice was "wrong." We all have experience that we've reached through various methods, techniques, life experience, and hard knocks.

Lets address the issue of "bulged cases." As M Brater mentioned bulged cases (not however mentioning how bulged they were), I suggested that bulged cases may indicate an oversize chamber, not knowing exactly how "bulged" his cases were. blitz99 mentioned that the Japanese did increase the chamber dimensions of their rifles as a result of experience gained during the Russo/Japanese War. Correct and to the point, yet this doesn't make the previous statement "wrong." And, there is a limit to the amount of acceptable "bulge" of a cases diameter. Not knowing exactly how much that bulge is with these cases (no dimensions have been given) a definitive answer is really not possible.

As for the issue of primers backing out, "most certainly" it is generally an indicator of low pressure in a cartridge, however it is not only that. It can be an indicator of excessive headspace as I have experienced twice with commercial rifles, with commercial ammo, during the last thirty years that I've been working on and repairing rifles. Both of these rifles had had a long "service life" with a lot of rounds and both were set back a thread and rechambered, solving the problem. No further issues with primers backing out with factory ammo, which both owners chose to use. Of the hundreds of rifles I've ever fired, with thousands of rounds, I've experienced a primer backing out from low pressure cartridge exactly three times, and that was from cartridges that were accidently reloaded with an undercharge traced to powder bridging in the measure. That was about the time I learned to look in each and every case before seating the bullet. Now I'm not an "advanced reloader" who enjoys making gallery loads or other low powered loads as I've never had the need or desire. I make my ammunition to a minimum of factory specs, with general factory pressures, with the original cartridge velocities. Thats my technique, and thats my desire. Others can and will have a different outlook, fine for them.

Then there is the issue of "undersized" ammunition. The majority of rifles discussed within these forums are military rifles, meant for battle, under the worst of conditions, with no thought of ever having the ammunition used ever being reloaded. One time use, no problem. That means that the ammunition produced is generally manufactured to the original makers cartridge dimensions. And, as this ammunition wasn't initially made to be reloaded, those of us that do reload them may experience some minor difficulties with those cases being "over worked" by resizing. So we have to make adjustments and perform different techniques to make these cases last for several reloadings. And there are some among us that want their cases to last forever. More power to them, go for it and have at it. In contrast there are those of us that just want their ammunition to work well, safely, and in any of our rifles. Different approach, neither is "wrong."

And as Accurate Powder reports Norma factory ammunition as producing 40,000 chamber pressures, I'm not too sure I'd call that "low-pressure loading in factory ammo."

http://www.accuratepowder.com/data/PerCaliber2Guide/Rifle/Standarddata(Rifle)/264Cal(6.5mm)/6-5%20Arisaka%20pages%20227%20and%20228.pdf


eb