260 ejection issue, Lapua brass

[Triple D]

All,

I've just recently had a chance to take out a rifle that was recently built for me. One thing that I've noticed is that it won't eject lapua brass. I've tried virgin and FL size lapua and it won't eject the cases consistently, loaded or unloaded(<5% ejection). The cases are just dumped on the follower. It's also a bit tougher (marginal) to chamber the lapua brass over remington brass. It will eject remington brass (100%). All brass is at the minimum trim to length tolerances. The lapua neck is at .292 on unfired brass, .294 on loaded cases and ~.295 on fired cases.

The second thing that was noted is that ejector marks are evident at 41.5gr H4350, which is the suggested starting load from the Hogdon website for the 142's. I realize that lapua is thicker, and I could have a hot lot of powder, but that doesn't explain the ejection issue. These were loaded up to test out the rifle and perform a break in.

Any insight would be greatly appreciated.

260 tactical match reamer, .298Nk with 0.088FB

 

[ARsR4ME]

Whats your fps on that starting load? A crono is just as important as a good scale. Not cronoing when working up loads is like driving blindfolded to me. I would also take the bolt out and see if when you place a piece of lapua brass in the bolt head and does the extractor go around the rim or is it just sitting on it. If it does go over it like it should, check the ejection rod under it and see if it seems to have sufiecent pressure to push the case out of the bolt head. Im not a gunsmith but thats where i would start.

 

[Triple D]

No chronograph was utilized. The minor ejector marks are very faint. In addition, the half moon mark also appears on unfired cases as well. The ejector seems to work as evident by the 100% ejection of the remington cases. Upon measurement, the lapua and remington cases have the same dimensions at the base. Granted, I only had time to measure 2 cases of each this morning.

The bolt body and face have been cerakoted FWIW. I'm mainly wondering if it is an extractor, ejector or headspace issue.

 

[ARsR4ME]

Rodger that. I would take the bolt out and put a remington case in the bolt head and look real close at the extractor. Then put in a lapua case. Im betting the glaw isnt going all the way into the grove to be able to pull the case out. Could be the creakote to. Thats a good point. Hopefully some one who knows this stuff will be in andhelp.

Eta. I took a quick pic of my bolt with a case. I can pull as hard as i want once the case is in and its not coming out. Can your do that or does it slip?

 

[leadbullet]

Simple, quit using lapua brass until you remove the paint on the bolt face and ejector and extractor
Cheers

 

[Crawlin]

Simple, quit using lapua brass until you remove the paint on the bolt face and ejector and extractor
Cheers

 

[RTH1800]

Need to hit the extractor with a small stone or file and cut it back a bit. Very common, more so with .223's If you look at the rim configuration on the brass the Win. is much thinner and ejects.

 

[Triple D]

Both cases extract. The lapua won't eject. I've placed both remington and lapua brass in the bolt with no real difference noted. The extractor seems to cover the rim on both cases when the bolt is out of the rifle.

There is no cerakote on the extractor or ejector.


Thanks for the replies, including comic relief! Please keep posting possible culprits, as I desperately want to have this issue resolved.

Really hoping Chad, George or Marc can add some input.

 

[nexusfire]

I couldnt go above 41 grains, and that is pushing it, with lapua brass and 139 scenars. Fucked up my ejector and trashed about $100 in brass if I went higher. Went to RP brass and 130 VLDs and it is a laser at 2810 fps with no signs of pressure.

 

[Triple D]

Pics from chambering rounds. Rounds were placed in the chamber and then the bolt was manipulated to lock the lugs and extract. Pressure was placed on the case during extract to ensure there was no additional contact with metallic parts.

Lapua up top
Remington on the bottom. The remington had been chambered a few times, hence the marks on the bullet from extract/ejection.

 

[ARsR4ME]

Thats weird man. I sure thought you would see a notixable difference with the bolt out. Good luck with it.

 

[ARsR4ME]

Hey,doing a really close up view of the the extractor claw it looks like one side is not machine right. The pic looks like one side has the lip like it should (top) but the other side is 2-3times as thick (bottom). Is that just the pic? I would take that bolt apart and look at it real close. Might be it

 

[nexusfire]

Kind of looks like you are touching lands.

 

[RTH1800]

Ok, one more time. It will not EJECT due to EXTRACTOR holding it too tightly. Look at the rims and note difference in rim thickness. Need to stone EXTRACTOR on inside edge or use Win brass.