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Posted: 11/28/2007 7:26:00 PM EDT
The extractor on my LR bites into the rim of the brass hard enough to raise and compress a piece of the rim the same shape as the extractor. It does enough damage that I can only get one firing out of my brass. once in a while it will tear a piece of the rim almost off. Is there a lighter spring that is available that will be a little nicer to my brass?
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| I had a problem with extraction in the begining when the rifle was new(200rnds ago). I polished the chamber wiht a boremop and Flitz, it worked great. The once fired GMM brass that I use is the most affected by this situation, it extracts but the rim is ruined. The Winchester brass I use, especially the nickle plated stands up a lot better, it can be loaded three times before i don't trust the rim anymore. I also don't think it is a high pressure sign because these loads are not exceeding 45,000CUP. The extractor bites into the rim very hard, I was wondering if this is the case with you other fellas. Thanks (sorry about the crappy cell phone picture) |
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If I understand what you're saying. The extractor spring is not strong enough to compress the rim of the case but, it will rip it when trying to pull the case from the chamber. There are 2 schools of thought on chamber "polishing" 1) Some say never use anything finer than 180 grit because the case should stick to the side of the chamber when it's under pressure so all of the pressure/thrust is not on the bolt. 2) The others say it should be smoothed but not a mirror polish so the case can be extracted even if the timing is off. This is mainly a combat trick for reliability. They also say carry a spare bolt just in case it breaks. |
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my DPMS308 did this as well. It was overgassed. I installed a JP adjustable gas block and it cleared right up. Looking at your brass, I don't think a simple chamber polish is going to work.....better to let DPMS take care of it under warranty. I'll add a +whatever--Shane is good people and will take care of the issue |
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