First, this has nothing to do with reloading. It has to do with (what I interpret as) a sign of high pressure. The question is how come?

The Occurrence: I fired a .22 Long Rifle round from a 2nd Model Single Shot pistol. I extracted the empty cartridge---and subsequently tried to put it back in the chamber. I don't remember why----perhaps as a "snap cap". It went back in only with some difficulty. It had to be perfectly aligned to enter the chamber---and was seated only with uncommon effort. (This was the first round I had fired in this gun---and I was puzzled. I had no intention of firing it again, and pretty much forgot about it.) It is worthy of note that the firing pin mark was all but invisible----could only be seen with magnification, in good light, and from just the right angle.

The Pistol: A MUCH MODIFIED single shot. The modifications of note are a VERY light weight hammer, a lightened hammer spring, and what I choose to call a "Hammer Damper"-----a shock absorber type device to reduce the effect of the hammer strike on your very delicate aim----such as it may be.

Okay, time passed. It became necessary to replace the hammer (another story for another time). I did so----and fired the gun again. It went bang. I extracted the empty, remembered my previous experience, and tried to replace the empty cartridge in the chamber. It went right in---no fuss, no muss, and no bother. HUH?!!!

The Ammunition: I'm not sure, but it was one of these three---most likely the first. (All of these are old---some are older than others.)

The First: Winchester Super-X, T22 Target (standard velocity). The number accompanying the bar code is 20892 100024----for whatever that's worth.

The Second (unlikely): Remington 22 High Velocity. Bar code number is 477403.

The Third (also unlikely): Remington 22 Long Rifle Brass Plated Hollow Points (also high velocity). The bar code number is 21250.

I've fired one each of all of these. All go right back in with the aforementioned no fuss, no muss, and no bother. It is perhaps noteworthy the new hammer is a little heavier than the old one, and the resultant firing pin marks, while still very light, may be seen without magnification, in pretty much any light, and from pretty much any angle.

End of story---except for one of you wise souls coming up with a reason why.

Ralph Tremaine

Common.

The brass once fired has expanded a little as has the mouth of the case, Brass will usually spring back to almost the same size but not really sure about 22 lr.

It's the reason when reloading center fire that the first step is to resize the brass back to the "normal" size.

I kinda skimmed all the other parts of the post, but if the gun goes bang every time, I would not worry. My SW revolvers I can not put fired 22 lr back into the chambers.

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Still Running Against the Wind

If the brass in the first case went almost all the way in before getting tight, it might have been the hammer, and the other modifications.

However, if the brass was tight all the way in, it might have been due to a dirty, fouled, rusted or etc. chamber/barrel. Or if the temperature was a lot hotter on the first shot than the second that could explain it too, as there are a number of reasons to get high pressures.

You have allot going on there, some of it I don't understand why you would want or make happen. But to each their own.

Sounds like that early target pistol has a bad/out of round chamber. It's actually fairly common for early 22lr firearms to have this.
A little 22lr 101:
Never ever use/shoot any high pressure/hv ammo in 22lr's made before 1926 unless it's well documented others have done so with the same firearm/era firearm you plan on using.

Why you would want lite hammer strikes on any rimfire ammo is beyond me. The only thing that will do is make any firearm/ammo combo inaccurate.

You replaced the hammer with one that was slightly heavier and your problem went away? The original problem was caused by the hammer.

You have a pistol that was modified to reduce the effect of hammer fall on your aim. These modifications appear to cause hammer to NOT press as heavily on the cartridge as it fires therefore there is more and longer case set back toward the recoil plate/hammer. This would cause the over expansion of the case and result in the difficulty reinserting the case in the chamber. The heavier hammer restored the delicate balance designed into the gun and fixed the over pressure.

I had the same problem in a antique 22 short single shot rifle some years ago. I didn't notice a bulge in the base of the sired cases till the third shot. Diagnoses was a weak hammer spring/worn parts in the action. The rifle was retired to the wall.

This is a long winded post to say if the new hammer fixed the problem the old hammer was the cause as long as that was the only thing you changed on the gun.

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Quando omni flunkus moritati.