Hello,

I have a new rifle setup for long range prone shooting. A Rem. 700 long action, Bartelin 30 inch barrel, 1-9 twist, Jewell trigger, 8x32 NightForce scope, B&C prone stock, in .284 Winchester. The long action enables seating the 162 grain A Max bullets "out".

This barrel loves 57 grains of 4831sc, in Lapua cases with CCI BR2 primers. The chronograph tells me that with a recent group the velocity was 2,832-8 fps for 5 shots. That group went into .287 at 100 yds. A problem?-YES! I had to beat three cases out of the chamber with my cleaning rod.

Reluctantly I reduced this load to 56 grains which drops the velocity to 2,780's. I have just returned from the range sighting in at 600 and I have a case stuck with this load.

The bolt has a speed spring in it for faster lock time and cocking is noticeably harder. I certainly can live with this if I could get those fired cases extracted and ejected. I keep the bolt lubricated; especially the cocking cam portion.

Any ideas? It would seem almost silly to keep reducing the load in a 30 inch barrel since shorter barrels are producing the velocity I am presently at now.

Thank you in advance for your attention in this matter.

Gene S.

quote:

It would seem almost silly to keep reducing the load

It would seem even more silly to keep beating cases out with a cleaning rod.

Are the cases the proper length?
If not, you'll just have to give up some velocity in exhange for more SAFETY

Your load 57gn load is a grain under max according to my data, although 2808 fps is probably getting towards max for the cartridge

However there is not enough information here to give you much advise. What do the cases look like? Are they heavily marked from the ejector hole on the case head? Can you measure them before and after with a micrometer?

You mention the barrel is new - are the cases new or had prior firings? How are you sizing the case?

I agree with Bwana. If excess pressure is causing the failure to extract, then there should be other signs of excess pressure I would think. Pictures of case head of extracted brass? Pictures of case neck etc. Others will know more than I.
Peter.

Is it a custom chamber? Tight neck? Take one of your fired cases and see if a bullet will slide into the neck; if not, tight neck. Either that or you are jamming your bullets into the lands.

how many reloads on the brass. I know you can reload the hell out of Lapua brass but how many are on them now?

Are you getting enough primary extraction?

I had the same problem with a custom Remington action built for me by Homer Strickland.It turned out to be a crack in the ejector right at the spot where it is riveted to the lip of the bolt

jazzpicker-
you mean the extractor not the ejector.

gene so-
as you've witnessed the lighter firing pin w/
heavier spring did nothing to decrease lock time.

As mentioned,if your brass is serviceable w/no signs,I'd concentrate/look at the chamber/throat thru a bore scope.

Maybe polish the chamber up. Is the brass hard to chamber? What's the head of the case look like? Are the bullets in the lands?

are the bullets seated so "long" that there isn't enough neck tension on the bullet to actually hold it and ignite the powder properly, in which case the primer is "firing" the bullet into the lands at which point you're getting a detonation type event? As mentioned above old cases with brittle brass/no neck tension could do the same...

For consideration- did you neck turn the extra shoulder brass that was on the lapua brass when it was 6.5-284 that you turned into the bottom of the neck when you expanded to 7mm? Is it possible that if you did not preform that step, that the extra brass here is causing the case to stick in the chamber. Just food for thought.

All the above posts are good solutions/questions but it appears that "gene so" isn't interested in what anyone has to say.

Why would a guy go to the trouble to post a problem and then never respond again?

Zeke

You might try a Sako style extractor.

quote:

Originally posted by ZekeShikar:
All the above posts are good solutions/questions but it appears that "gene so" isn't interested in what anyone has to say.

Why would a guy go to the trouble to post a problem and then never respond again?

Zeke

Gotta wait until next year to find out, 5 posts in 5 years (hahahaha)