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<Rifleman7>
posted
appear to be as smooth as it should in my .308. I would take it back to the fellow that smithed it but it's about a 6 hour drive. The brass has some parallel makings on them after firing. Even mild loads are hard on bolt opening. I've checked about everything I can think of. Unfired brass chambers and extracts like silk. The bolt is just real hard to open after firing. The gun has a minimum chamber with a .339 neck so I'm real carful to measure necks after loading to make sure I've got .337. Bullets are usually seated .010 to .020 back from its jam figure. The stupid thing is that the rifle shots. 175 Match Kings will print in the mid twos for five shoots. The big question is - is there a home remedy I can try to smooth the chamber to see if that cures to hard bolt problem?
 
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Picture of D Humbarger
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Those parallel marks sound like reamer chatter to me, but I would have to see a fired case to be certain. Thats a bad thing.

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NRA Life member

 
Posts: 8351 | Location: Jennings Louisiana, Arkansas by way of Alabama by way of South Carloina by way of County Antrim Irland by way of Lanarkshire Scotland. | Registered: 02 November 2001Reply With Quote
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Rifleman,
I would have a gunsmith look at that rifle before firing another round in it.
The marks on your brass are bad enough, but if even mild loads cause sticky bolt lift, you may have a serious headspace problem.

George

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Shoot straight, shoot often, but by all means, use enough gun!

 
Posts: 14623 | Location: San Antonio, TX | Registered: 22 May 2001Reply With Quote
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Rifleman, contact the gunsmith. He should make it good and I agree, don't shoot it until it is checked out.
 
Posts: 4917 | Location: Wenatchee, WA, USA | Registered: 17 December 2001Reply With Quote
<Lee S. Forsberg>
posted
quote:
Originally posted by Rifleman7:
appear to be as smooth as it should in my .308. I would take it back to the fellow that smithed it but it's about a 6 hour drive. The brass has some parallel makings on them after firing. Even mild loads are hard on bolt opening. I've checked about everything I can think of. Unfired brass chambers and extracts like silk. The bolt is just real hard to open after firing. The gun has a minimum chamber with a .339 neck so I'm real carful to measure necks after loading to make sure I've got .337. Bullets are usually seated .010 to .020 back from its jam figure. The stupid thing is that the rifle shots. 175 Match Kings will print in the mid twos for five shoots. The big question is - is there a home remedy I can try to smooth the chamber to see if that cures to hard bolt problem?

What action are you using?

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LSF/375

 
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I think you have a chamber that is insufficiently polished.

I had such an experience with a new Remington 700 Limited Classic in 300 Weatherby when it came out some years ago. The fired cases from all loads, including factory loads that I knew were not over-pressure, stuck so strongly in the chamber that I had to pound the bolt open.

I solved the problem myself, with a rough-and-ready method that worked successfully. I got a 1/4 inch wooden dowel rod, cut it to about 18 inches, and wrapped about 1 1/4 inches of the end with emery cloth, with a pad of thick rubber band under the cloth to provide a "cushion" or "spring" that would push it outward. I made this in a layer, with the emery cloth on top of the rubber band. I stapled the end of the emery cloth to the dowel, and then wrapped it on the dowel by turning the dowel rod in my hand. (You have to make this by turning it in the direction -- clockwise, looking down the shaft from the non-emery end -- that will cause it to not bunch up when you put it in the chamber and turn it, as I describe below.)

I then put the other end of the dowel in an electric drill, and put the emery-covered end into the chamber of the rifle. I then turned the drill on, and used the emery in the chamber for a bit, moving it in and out so it would not rest at any particular point. Afterwards I took the emery off of the dowel and put a wad of steel wool on it and used this in the chamber to finish the polishing.

After this, the rifle worked like magic. No matter how hot a load, cases always extracted without any problem, like a hot knife moving through melted butter!

I wrote to Remington about it, and they replied that what they would have done was the same thing as I did -- polish the chamber. When I told the dealer who had sold me the gun about it, he said that having a new gun with an insufficiently polished chamber is not uncommon; according to him some even have visible tool marks in them. He mentioned that there are some autoloading pistols, for example, that will rip the rims off of cartridges that stick in their chambers.

[This message has been edited by LE270 (edited 12-27-2001).]

 
Posts: 5883 | Location: People's Republic of Maryland | Registered: 11 March 2001Reply With Quote
<Rifleman7>
posted
Lee, It's a Rem 700 short action. It's blue printed, Lilja 3-groove HV 26" barrel, McMillan pillar and glass bedded stock. The marks on the brass are somewhat random in nature. Almost like scratches from running something in and out of the chamber. It's not scratches from loading. Those types of marks are different. Here's the strange thing, Lapua brass is harder on opening than Federal using the same load - 42.8 of RE 15 with 175 Match Kings. That load shoots in the mid twos for 5-shots. Could it be that the Lapua is softer and flows into the scratches more than the Federal??? I've unscientifically checked the head space using Scotch Tape on the case head. It doesn't appear to be too much or little. Measuring fire formed rounds compared to published data shows dead on. As I said earlier, I'm checking for neck clearance and am back off the jam figure .01 to .02. I'm having a hard time figuring that I'm over pressure. It might be. However in a .308 VSSF that I hunt with , I load 46.5 of RE 15 with Hornady 165s that chronograph 2950 fps. Fired rounds unchamber like silk and the brass is cool to the touch. What's up with that?
 
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<Don G>
posted
I suspect you might be pretty hot there!

QuickLoad says you are hitting 66,000 PSI. I'd back off to 44 grains and work up slowly.

Every rifle is different!

Don

 
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<Mike Dettorre>
posted

What are velocity are u getting out of the 175 matchkings.

Regardless of powder charge and loading manual specs, cetris paribus, higher velocity means higher pressure.

I would think that anything over 2800 fps form a 26" for a 175 grn bullet from a 308 Win would be generating pressure troubles.

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MED

The sole purpose of a rifle is to please its owner

 
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<Rifleman7>
posted
In my last post responding to Lee, I gave a description of the .308 tactical rifle that I'm having problems with hard bolt opening. But I also have another .308 that I hunt with. This is a 700 VSSF fairly box stock. The load I use in that is about as much as one can get and still keep it all in one piece. I've shot a bunch of them with no signs of high pressure - primers look fine, bolt opens easy, cases are virtually cold to the touch, barrel gets mildly warm. On the tactical gun, I have not chronographed any loads yet. Even mild match loads with 168 SMKs have a hard bolt open. But after all of ya'lls input, I believe the chamber lacks a fine finish and I will return it.
 
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