Thread: Very hard extraction.

Originally Posted by Friwi

Hold on, the gun on the video was a right hand gun and this one is a left hand one? What is up with that inspector gadget?

The one in the video was a Remmy 700 that I found on YouTube that was a good representation of easy bolt lift but hard extraction. Of course the one here has the bolt on the wrong side for TR.

How bad would the cure be? I'd say the bolt body would need to be shortened and the bolt handle wound a bit closer to the bolt head.

Here is the one with the bolt handle on the wrong side.

I can assure you that is the right side, gadget!

(sinister laugh bahahaha)

Originally Posted by Mauser308

Check the timing angle on the bolt handle with some marker pen etc on the contact surfaces. I would suggest the issue with the piece lies in the chamber and not anything to do with the primary cam angles - the empty case should extract without that much of a ballsup. You could relocate the cam angle with a bit of shaped steel and some superglue if you think that it might solve the issue but I'd put money on the fact that it's a chambering issue.

I've had experience of a couple of BRNO's that had no issue with cam timing (forged bolts and receivers so no chance of the bolt handle going on in the wrong place) that both had this issue, had to pop the fired case out with a rod (major pain in the arse and high potential for a clusterfuck). I've got a Rem700 here that has poxy timing but no issue with primary extraction (relying on the cocking surfaces with the typical massive 'CLICK' as the handle extension cam surface comes into contact) - that's in a .308.

Remington gets a bad rep for this, honestly I've had a lot of rem's but I've had more issues with Chinese and Euro guns (and more than the fair share of NZ rebarrels to be brutally honest).

I agree. The bolt initially moves back as it should. I can see marks on the walls and neck of the brass where it has scraped with extraction. I suspect that there is gummy muck in the neck area of the chamber by the goo on the neck of the clean brass that goes in. Wondering how a military 308 brush would go for a good scrub out?

Only the last 1/4-1/3 if the cam seems to make contact, but I suspect that it is caming off the locking lugs.

Originally Posted by 300CALMAN

Video not playing.

Sounds like a slight bur in the chamber if there's a line left on the case.

One of my rifles leaves the faintest of marks on every fired case. This doesn't cause any issues for me and I use it to count how many times a case has been fired. But if it were more pronounced, I could see it causing a real issue, as each time the case is extracted it may have to break/shear free of the indent.

Shove a borescope up there to have a look.

Here's a pic of my case, look carefully on the shoulder and you see the imperfection that my chamber must have, and the corresponding line it prints on each case.



If it were more pronounced it would be a real issue, but it's not significant enough to cause an issue in my rifle.

Post a pic of your case so we can see what's happening.

Originally Posted by kimjon

Here's a pic of my case, look carefully on the shoulder and you see the imperfection that my chamber must have, and the corresponding line it prints on each case.



If it were more pronounced it would be a real issue, but it's not significant enough to cause an issue in my rifle.

Post a pic of your case so we can see what's happening.

I think yours is worse. Been trying to get a good photo, will try again with a better camera today. Still think it is more an issue with a tight and gummed up neck. I looks like dried up oil that gets left on the brass.

Goorie looking shoulders shouldn't cause extraction problems - the case can virtually fall away from the shoulder.

Just out of interest GM will a projectile fit into the neck of one of your fired cases?

Originally Posted by zimmer

Goorie looking shoulders shouldn't cause extraction problems - the case can virtually fall away from the shoulder.

Just out of interest GM will a projectile fit into the neck of one of your fired cases?

I can get a projectile into a case from my Zastava 7mm RM but not in one from the Browning 7mm RM. OD of the necks from the Zastava are 8.10mm and from the 8.06mm.

The photo below shows the brass from the Zastava at the top and the Browning at the bottom. Both loaded from clean new Norma brass. The stuff once it finally gets beaten out of the Browning is very dirty on the neck. I have heard that there were a number of these Brownings that has tight chamberings. The loaded rounds chamber and extract fine without firing.



The marks on the brass are really pretty minor and very hard to photograph.

My moneys on primary a extraction issue

Originally Posted by gadgetman

I can get a projectile into a case from my Zastava 7mm RM but not in one from the Browning 7mm RM. OD of the necks from the Zastava are 8.10mm and from the 8.06mm.

The photo below shows the brass from the Zastava at the top and the Browning at the bottom. Both loaded from clean new Norma brass. The stuff once it finally gets beaten out of the Browning is very dirty on the neck. I have heard that there were a number of these Brownings that has tight chamberings. The loaded rounds chamber and extract fine without firing.



The marks on the brass are really pretty minor and very hard to photograph.

Most likely my eyes but there looks to be a shit ton of runout on the bottom cartridge?
Is there any feel difference when chambering.

I reckon primary extraction could be the issue as well. Is it a light load?

Sent from my SM-G935F using Tapatalk

Originally Posted by R93

Most likely my eyes but there looks to be a shit ton of runout on the bottom cartridge?
Is there any feel difference when chambering.

I reckon primary extraction could be the issue as well. Is it a light load?

Sent from my SM-G935F using Tapatalk

Just an optical illusion on run-out due to poor lighting and angle.

Will knock up a shim to place between the bolt and receiver and see how it behaves as a test. Think the chamber needs a good scrub too.

Load is 71.5 gr of 2217 pushing 162 gr A-Max out of brand spanking Norma brass and CCI magnum primers. Zero signs of over pressure.