Zermatt Rim X failure to fire

[smelv]

Hi y'all, have a look at ANSCHUTZ KERAMIK COAT ,temp range -40c to +750c.I have been using this product for approx 2 years in an anschutz 54.30 target rifle, even in the bore during storage. Slicks everything up and makes bore cleaning much easier.Some videos on UTUBE are worth a look.Tongue in cheek!!! we are lubricating precision instruments not heavy machinery.Scott.

 

[orkan]

But as I was typing that it occurred to me that the increase in lock time really wouldn't matter when the ambient air temp is well below freezing because rimfire accuracy goes to hell down there anyway. So it wouldn't matter...

You forgetting my 6x5's I shot when it was in the 20's?

 

[jbell]

You forgetting my 6x5's I shot when it was in the 20's?

I must be, did you shoot it this year? I’ll go look for it. For sake of clarity when I said it really wouldn’t matter b/c rimfire goes to hell in air temps well below freezing I simply mean that the percentage of accuracy loss from the extreme cold would be greater than the percentage of accuracy loss from a slightly longer lock time caused by a higher viscosity grease in the bolt shroud. IMO the addition of a lubricant in the bolt shroud is only applicable / noticeable when you get to the point of trying to extract the last bit of accuracy from your rifle (it is small gains at that point).

 

[flatland1]

Jesse,
Was your RimX chamber modified with a slight ramp cut at 6:00? I tried experimenting with raising the mag latch on my two magazines late yesterday afternoon, and found that mine won't feed at all unless the mag latch is adjusted for no more than the recommended max of 1/16" play. After that, I decided my next move will be to pull the bbl again, and set it back at least .050", then run a new JGS carbide M52D Match reamer in, which I hope will smooth feeding a bit.

 

[jbell]

I don't think there is a ramp cut into the breech, I'll have to look closer when I get a second. I'll post a picture if I can get a good one.

 

[orkan]

I must be, did you shoot it this year? I’ll go look for it. For sake of clarity when I said it really wouldn’t matter b/c rimfire goes to hell in air temps well below freezing I simply mean that the percentage of accuracy loss from the extreme cold would be greater than the percentage of accuracy loss from a slightly longer lock time caused by a higher viscosity grease in the bolt shroud.

I once believed that as well... however, this years results have caused me to question what I thought I knew. My initial submissions to the 6x5 were in april time frame... and were both in the .2's if memory serves. I'm now leaning more toward rifle configuration being to blame for poor performance in cold. ... because it was pretty windy on this attempt, and it still was hanging right in there.

Here's one from april at 24f. ... and this was before I put a tuner on the rifle.

 

[padom]

From my sub freezing rimfire testing this year, I have found the ammo (like all 22lr accuracy right) plays the biggest part in accuracy and even more so when its below freezing. This was shot at 300yds, 0-5mph wind, snow on the ground, temps right at 20F shooting Federal UltraMatch back in March. Other ammo I tested, good luck below freezing.

10 shots, first one off the right edge of the plate, make a wind correction, 9 on the steel, another wind correction, 8 on the center reactive plate.. 9 are moa, 8 are sub moa.. and those 7 after the final wind correction are sub 3/4 moa. Not bad but the ammo was the single biggest factor. Now that I am officially out of my stockpile of UM22, time to start lot testing ammo with winter fast approaching as this CX, while downright amazing, didnt hold a stick to the UM22 below freezing in my testing. Since my last batch of UM22 was made by RWS and stamped RWS R50 under the box tab, Ill be lot testing R50

This was shot with my custom 20" Bartlein CZ455 with Rugged Oculus 22 and UM22

 

[orkan]

While I agree ammo is a critical factor, and one of the reasons why I shoot R50... it would seem there is quite a bit of rifle variable as well. I think I have the main couple variables nailed down, but I'll do some more testing before revealing my thoughts there.

Well... looks like I have something to do this winter. With any luck it will get cold cold before the feet feet of snow shows up.

 

[padom]

While I agree ammo is a critical factor, and one of the reasons why I shoot R50... it would seem there is quite a bit of rifle variable as well. I think I have the main couple variables nailed down, but I'll do some more testing before revealing my thoughts there.

Well... looks like I have something to do this winter. With any luck it will get cold cold before the feet feet of snow shows up.

I agree, and what Im saying is if the rifle is squared away, the ammo is the deciding factor at that point in my testing to date. What I didnt state above, is that was not shot with my RimX. That was a 100% custom CZ 455 I built. I also look forward to testing my RimX (my same chamber as the CZ posted above) in the cold weather this winter.

It was a CZ 455 action, fully polished bolt raceway, polished bolt, Don Smith DJ firing pin spring, BScar 2 Stage trigger set at 8oz, custom 20" Bartlein 0.900" barrel I had custom headspaced and tenon fit to just shy of press fit to my action that I glued into the receiver and chambered with my 22 Match Eachus chamber. MDT ACC 455 chassis that I Devcon bedded the barreled action to the chassis. It loved that UM22 at any distance out to 500yds.

 

[jbell]

Jesse,
Was your RimX chamber modified with a slight ramp cut at 6:00? I tried experimenting with raising the mag latch on my two magazines late yesterday afternoon, and found that mine won't feed at all unless the mag latch is adjusted for no more than the recommended max of 1/16" play. After that, I decided my next move will be to pull the bbl again, and set it back at least .050", then run a new JGS carbide M52D Match reamer in, which I hope will smooth feeding a bit.

No ramp cut:

I put a dial indicator on the magazine in 3 spots front, middle, and rear and found right now it is at the 1/16" of vertical play. This is where I left it the last time I was messing with it at the range when I didn't have a way to measure it. The magazine catch is almost all the way up. I am still getting a few rounds to chamber poorly causing a flyer, like 3-4 out of 50.

 

[RTH1800]

This thread has drifted but the real issue is if your rimfire will not fire with a dry bolt, firing pin, spring, sear etc. it needs fixed, not stuffed full of grease. Even “special fancy NASA” grease. Then lightly lube it with silicone or oil and drive on.

 

[drglock]

No ramp cut:
View attachment 7433700

I put a dial indicator on the magazine in 3 spots front, middle, and rear and found right now it is at the 1/16" of vertical play. This is where I left it the last time I was messing with it at the range when I didn't have a way to measure it. The magazine catch is almost all the way up. I am still getting a few rounds to chamber poorly causing a flyer, like 3-4 out of 50.

View attachment 7433704

That’s completely opposite of mine and might just be the difference in the bottom metals. I’ve got mine set with the mag as high as it will sit in mine and still lock up on the mag catch. Only thing on mine that makes it a bit hard to close is the tensioner but it’s not that bad I’m just nitpicking.

 

[jbell]

I am going to try a different stock / chassis my next time out and see what difference if any it makes. After that I have another suggestion that I want to try that sounds great. But one thing at a time...

 

[flatland1]

I had time this afternoon to pull the Bartlein from my RimX and get it dialed-in again on the lathe so I could set it back .050". Since I'd already CeraKoted the bbl & then engraved '22LR' on it, I wanted it to index so the engraving would still be right; 1 divided by 20tpi = .050", so that's how far I set it back. I'd decided to go with a Win M52D Match reamer to see if the taper from .2273" at the rear to .2259" at the throat would improve feeding. Borescoping after I'd finished the chamber revealed that .050" set-back had also allowed the 52D reamer to completely re-cut the previous EPS chamber. The wind had been fairly strong at 20-25mph most of the day, but by the time I'd finished the job and got the rifle back together, it'd died down to 10-15mph out of the north. I just had time to take it out to my smallbore range and put it on steel at 100yds - it's normal to move the POI a bit after taking a rifle completely apart, cut a new chamber, and then put it back together, but that wasn't as important to me as finding out whether switching to the 52D chamber would improve feeding. I put a quick two magazines of some old Wolf Match Extra that normally doesn't shoot very good through it to get a feel for feeding, and was pretty pleased - it fed quite a lot smoother and it seemed to be off my normal 100yd come-up by only .1 mil in windage, with elevation being pretty much unchanged.

This 52D Match reamer doesn't have the radius at the body/rim transition that my EPS reamer does, so I cut a 45* bevel at the edge of the chamber that was about .020" wide, then polished the corners of it pretty thoroughly with a cratex rod. Hard to say if the dimensions of the reamer or the bevel was most responsible for the improved feeding, but when it comes down to it, I was happy with it, and at this point, don't really care - pending a day with decent conditions so I can shoot groups at 50yds and compare them to the ones the EPS chamber produced.

 

[jbell]

I look forward to hearing the results when you get some better conditions.

 

[padom]

Just posted this in the RimX thread but Ill repost here for some of you as well



Finally got around to testing 2 new lots of CenterX and a new lot each of SK+ and SK RM that Ive had sitting here for a few months. Shot 3-10 shot groups of each at 50yds out of my Keystone Accuracy Krieger with my 22LR Match Eachus chamber all with my Rugged Oculus attached.

These new lots were very consistent, I am very happy with them for 10 shot groups shot fast. I recorded every shot at the firing line for some of you who are having issues feeding, etc. to see how smooth and fast my combo is running. I shot all 120rd in a row, only stopping was to load mags and hit the stop and play button. Not a single hiccup, feeding issue or hard bolt close. Smooth as glass and I can run it as fast or as slow as I want.

Im going to put together another post for some tips/instructions for you guys having some feeding issues or shaving lead on feeding..

20" Keystone Accuracy Krieger M24 threaded 1/2-28
XLR Envy Pro
BixN Andy TacSport Pro 2 Stage
Rugged Oculus
Atlas Bipod
Precision Underground 3D Rear bag
Athlon Ares ETR APRS1 MIL

 

[jbell]

padom, that is what I am after. Your rifle looks as smooth as Greg’s does and as smooth as all the Vudoo’s I have shot, which if I am being honest is what I am judging the RimX against. I am sure I’ll get there with this rifle, I just need to find the time to dedicate to working with it.

Thank you for your suggestions on the chamber, and thank you to everyone who has contributed to this thread so far.

 

[Budlight]

I started down the road of fitting the trigger to the action today. First I measured the current cocking piece height to the top of the shroud directly adjacent from the cocking piece (using the fixed anvil of my mic and the round portion of the cocking piece as a reference, to be repeatable).

First measurement before starting:
View attachment 7422451

Witness marks of dragging on the sear:
View attachment 7422453

Witness marks on the cocking piece:
View attachment 7422455

First round of fitting, honing the cocking piece on a flat diamond stone:
View attachment 7422456

Testing the fit using a sharpie and a few dry firing, still dragging:
View attachment 7422458

Remove a bit more:
View attachment 7422461

Still too much contact:
View attachment 7422462

Removing a little more:
View attachment 7422463

Looking pretty good:
View attachment 7422469

We went to the range and put 160 rounds through it with no FTF! There bolt lift and close was much easier, not as easy as the Vudoo but much better! The accuracy seems pretty good but after 160 rounds I think there is a little room for improvement, still slightly dragging (it was polished to a mirror finish on my ceramic stone, you can clearly see the witness marks):
View attachment 7422473

I’m having FTF issues on WSM. Do I hone the entire colored area on the slide?

 

[jbell]

I’m having FTF issues on WSM. Do I hone the entire colored area on the slide?

I would confirm the problem first. I would not assume it's the cocking piece excessively dragging on the sear. Maybe you have already?