Citadel M1-22 Carbine

[Sentryduty]

It looks good, but the feeding is flaky. The Erma has a habit of ramming the cartridges into the base of the barrel - i.e. it feeds too low. Tuning the magazine lips helps, but still not 100% reliable.

I have been thinking about this problem, and I think I have a solution that may be allow a quick check. If the rounds are striking the base of the chamber, perhaps your could try increasing the feed angle upwards by shimming the front of the magazine follower, many .22 autoloaders have fairly extreme angles of attack on their followers. This could be done with some creative non-permanent means like a small scrap of wood or brass stock and some glue, that way if it didn't help, or made things worse it could be undone. If it worked you could investigate some silver solder work or bending the follower to suit.

[Sentryduty]

This evening I disassembled the bolt and decided to undercut the extractor to allow more engagement. Work was done with a tiny square diamond file and a sharp eye.

I took the undercut from a thickness of 0.113" to 0.105" for a total change of -0.008"

Testing by hand, initial extraction is now 100% but I now understand that if the action cycling is slow, the cartridge can fall out of the bolt face towards the magazine which will cause the extractor to be unable to grip the round. This will withdraw the casing about 1 cm and then lose grip causing a malfunction.

Without cutting in dual extractors or a bolt face redesign the only way to combat this is the rely on the extraction of the blow-back action.

If stoppages continue, I believe running higher velocity ammunition will keep the gun cycling with a brisk blow back impulse.

Photos are attached below, range testing to follow.

[Sentryduty]

Giving this design and overnight bit of thought, I think the whole issue could have been avoided with a shallower cut of the bolt face at the factory. If the bolt face were shallower, imagine a round disk style shim behind the cartridge base, then the extractor would maintain positive grip and control of the cartridge at all times. As designed the round is a loose fit in the bolt face and simply relies on inertia and blowback to do the work.

I suspect this is either a production oversight, or done to make the rifle more tolerant of assembly line part variations.

[browningautorifle]

This is why the foot dragging on my part. I bought a S&W M&P early and had problems that are now sorted out. This carbine I think will run the same gamut. The undercut may well sort you out though.

[Sentryduty]

This is why the foot dragging on my part. I bought a S&W M&P early and had problems that are now sorted out. This carbine I think will run the same gamut. The undercut may well sort you out though.

I understand completely, the SIG Mosquito was much the same, it was a great little gun, until it broke, and then it wasn't. I am just glad it wasn't mine or in my hands when it did break. One of the problems I find with .22 LR guns is that they are made at a price point, because few will pay "fullbore" price for a "smallbore" and clones based off of fullbore designs have to rely on lighter weight parts and springs to cycle with the much smaller recoil energy.

With this rifle, I will test with more of the same ammo, and with some HV stuff, my go to is usually CCI maxi-mags and the like. If I still have troubles, I will look to polishing the chamber to hopefully reduce extraction effort and polish the hammer face to reduce drag during the recoil cycle. As it stands the hammer face does drag on the bolt retraction a bit. A guy could look to trimming the recoil spring a bit, but I am concerned with buggering up the blow back as the spring is the only form of "locking" on this design.

In reality, it appears that I am attempting to make blowback extraction as fast and efficient as possible, all of which is a Band-Aid to cover for the poor cartridge control by design. As another standpoint, the rifle does have less than 100 rounds through it, maybe this is all "teething" issues from initial break in that will go away once I get the round count up. Hard to say, but even the bottom grade Norinco's 22's haven't been this fussy out of the box, and I don't think my expectations are off line.

[Patrick Chadwick]

This could be done with some creative non-permanent means like a small scrap of wood or brass stock and some glue, that way if it didn't help, or made things worse it could be undone.

An excellent idea, especially since it can be tried out with a reversible alteration.

[Sentryduty]

Would it be possible to see some photos of the Erma feedway Patrick? I have never dealt with one, and google is not forthcoming with photos of the area. As an exchange I can provide photos of a couple of example magazine followers and attempt to measure their round presentation angles this evening.

[Patrick Chadwick]

As designed the round is a loose fit in the bolt face and simply relies on inertia and blowback to do the work.

These observations from my testing of the Erma may throw a light on the problem ,as they seem to matching with what you wrote:

"Z" (Zimmer=saloon ammo) will not feed the first cartridge (hand release) - the short nose falls down before it reaches the chamber mouth.
Normal .22 - some do, some don't feed. All have unreliable auto-feeding.
CCI "Stinger". Hopelessly unreliable. The case seems to be longer than standard, and it couldn't chamber completely, ot if forcibly chambered by hand, wouldn't extract.
"Swartclip". Wouldn't lock up, until I realised that the copper-plated bullets are slightly waxed, and in near-zero temperatures the wax was so stiff that the cartridge couldn't enter the chamber properly.
So I scraped off the wax with a fingernail, and - hey presto! - it worked much better than everything else.

Finally, a friend gave me some Federal ammo to try out. The plain lead version was useless. Many ignition failures in both his AR15-clone type and my Erma M1, but then I tried:

Federal Champion '745. hollow-point, 36gn , lead, but copper-plated. V0 = 384 meters/sec.

This all (15 shots) fed and auto-loaded perfectly, so I have now ordered a "brick" for extended trials with different magazines.

Conclusions: the Erma will only tolerate absolutely "dry" cartridges with fairly-close-to standard overall length and case length. This probably indicates that the chamber has a tight tolerance. And the powder charge must have a bit more (slightly faster?) charge than "standard" plinking ammo.
It seems that these .22 auto-loaders are marginal in their operation, with very little reserve, so what you are doing to reduce frictional losses is surely a step in the right direction.

[Sentryduty]

I have found that Federal copper jacketed 36 gr. "bulk" is good benchmark ammunition for most rifles. The powder control is decent, varying by about 0.06 grains over 5 pulled cartridges (1.38 - 1.44 grains of powder) and is exactly the same QC as their Federal Premium Target, albeit at a lessor charge of 1.00 - 1.06 grains and a heavier bullet at 40 gr.

By contrast, any wax coated lead bullet cartridge tends to really give most autoloaders a hard time, this appears to be due to the wax gumming up the works. Bolt actions on the other hand are easy feeders.

[cipherk98]

I'm really enjoying this read and wish you success in getting it feeding well! Like some others I was turned off by reports of feeding issues and the fact I'm cheap so I gravitate towards Marlins, but I honestly wouldn't mind having one at some point for plinking with open sights. They're cool looking and at a pretty fair price for a .22 based off a more famous military arm.