Issues Feeding CEB Solids

[michael458]

I would PM @michael458.
He did a lot of development work on CEB bullets and knows Winchester M70 rifles.

I’m going to take my gun to a good smith this week but I don’t know that it’s something I will be fully trusting by September.

The CEB #13 Solid and the current North Fork Solid were designed around the Winchester M70 Control Feed Action.

I own, shoot, and hunted with nothing but Winchester M70s from day one. I apologize somewhat for my selfishness, but when designing the #13 my main focus was the M70 Control feed, and not much else.

We know meplat size is of the most important factors in Terminal Stability of a Solid. We know that 65% meplat of caliber is the breaking point of that stability, below that, stability during terminals suffers greatly, above that, in calibers .458+ a bullet can actually self stabilize to around 90% of its total depth of penetration, with no rifle twist or engraving. 416 caliber has a bit of a tougher time at it, and actually needs a faster twist rate of 1:12 to be 100% Stable during terminals, because of actual meplat physical size.

We tested from 65% to 70% meplat for the M70s. At 70% some guns would start to have issues. Finally settling on 67% meplat for the CEB and North Fork went to 68%, giving 100% reliable feeding in all M70s I had, which entailed anything from .416, .458, .474, and .500.

I had several M70 416 Remington over the years, and never had one that suffered feeding issues with either CEB or North Fork, even straight out of the box factory, and the same with 458 Winchester and 458 Lott.

I assume that @lil 2 sleepy rifle is a control feed gun, I have not heard otherwise or missed it. Any Push feed gun will have difficulty feeding these.

Also, I am no gunsmith or expert in anyway, fact is, I probably destroy more than I fix. But I have been lucky from time to time, simply changing parts out and achieving success.

From what I am seeing above, I believe the issue will be a matter of 3 possible issues. Spring, Follower and Extractor. One comment might lead one to think that the extractor is too tight, giving a push to the cartridge before sliding up under? I tend to think it is more in the Follower than anything else, and perhaps a new spring is in order too. There is something between these three components that is not interacting properly that is causing this, in my humble opinion.

I have seen many times in my Super Short series that the spring will get too much forward in the floor plate...... This causes the cartridge to point downward, and absolutely will not feed anything at that point. In those cartridges we pinned the spring in place in the floor plate to keep it from shifting during recoil, but I have never seen that issue with 416 Remington, 458 Winchester or 458 Lott.....but anything is possible I suppose, check the position of your spring in the floor plate, very simple......

The best advice I have is a competent gunsmith, and I would discuss these three items with him, most likely a change in these will give the desired results. I doubt that any serious grinding metal is going to be required at all.

Those that have other rifles that are not Winchester Control Feed guns, and have issues, you are going to need a gunsmith to sort that out for sure and I can't be of any help at all with CZ or others............ sorry.

 

[michael458]

My M70 375 seems to have a little less slop and looks like it would do better than the .416 with the CEBs

Reading this, you have in your hands a very simple test, the bolts and bolt face is the same for the 375 as it is the 416, the 375 bolt will work in the 416 Remington, try the 375 Bolt in your 416 Remington and see what happens, if you still have that issue, then change the springs and follower out of the 375 into the 416 and see what you get.............

 

[lil 2 sleepy]

Thank You Michael that is very good information.
They both are CRF. I have never run the serial numbers to see if it a New Haven model or not as others have asked.

I will swap the bolts later today. I have done that for other issues in the past, but it didn't cross my mind.

 

[Hunting Hitman]

Just to add nothing to the conversation …my Blaser R8 Selous push feeds 458 Lott 500 grain CEB’s flawlessly

HH

 

[michael458]

I will swap the bolts later today. I have done that for other issues in the past, but it didn't cross my mind.

After that, and still issues, swap the spring and follower as well...........

 

[jwp475]

I a 416 Remington and 458 Winchester in MarkX Mauser actions, the 458 Winchester feed the copper 380 grain bullets without fail and it has a larger meplat than the CEB

 

[lil 2 sleepy]

I swapped the spring, follower, and the bolt and I am still having issues. It did appear the fit was a tiny bit better in the box and the right-side cartridges fed perfectly.

The 2nd cartridge just hits the ramp and comes off at too much of an angle. It tries to get straight and does slide by 25% of the time. Maybe the gunsmith can do a little work and get it straightened out. I feel like we are taking hundredths of inches but it's not acceptable without some help.

I will make an appointment and see what he finds.

 

[Nhoro]

Please check something for me. Look at the bolts face on the left side. There is a collar or wall that encase the cartridge base and it is ramped on the left edge for the case to slide up and centralise. Feel the edge and the ramp. If it is sharp, it doesn't let the case slide up easily and keeps the cartridge down in the magazine so it dives right too far. The extractor does the same on the right side and both need a nice radiused edge and polished ramp. You can use a dummy round to see if the case rides up the bolt face or hooks there. I just use a small file to radius the ramp and fine sandpaper to polish it up. I did a writeup with some pics- Thread 'Mauser Action Feeding Work - CZ 550' https://www.africahunting.com/threads/mauser-action-feeding-work-cz-550.47094/

It only takes a rough edge or fraction of a mm in the wrong place to mess up the feeding of a flat nose. Round nose or spitzers tend to ride the ogive into the chamber.