I am not familiar with any +P ammo for 22lr. However, that doesn't mean it don't exist.

When I think of +P 22 ammo, I think of 22mag.

 

I believe it is commonly called "Hyper Velocity". I have seen some warnings about firing it in match or Bentz chamber rifle, as they are tighter than standard chambers.

 

 

I believe "Stingers" are still the fastest (or near the fastest) .22LR round.

 

The problem is the "P" in a centerfire is for "Pressure". But .22s have always been quantified by velocity. But yes, the high speed ammo that came out in the 1930s was higher pressure, hence not warranted for the original Woodsman, among other guns. Hi Standard shooters get wrapped around an axle trying to figure out what velocity is "too fast" for some of those pistols (that can crack frames), thinking being subsonic is "low pressure" but over 1150 is "high", and other hypothesis' that are just guesses. Somewhere the SAAMI pressures for .22's are listed, and that will tell you what is "+P" from the original rounds. This gives a good breakdown of Standard, High, and Hyper velocities (but not pressures) https://en.wikipedia.org/wiki/.22_Long_Rifle.

 

If you can find some, try the old Winchester 'XPediter' 29 gr. They're quick.

 

They sure don't group too well though lol. I burned some of this up a couple of years ago and I couldn't get a group out of it in any 22 I own. It was sitting on my dads shelf when I cleaned out his stuff

 

CCI Stingers are 32 grain, 1640 fps. CCI Mini-Mags are 36 grain, 1260 fps.

 

Thanks folks for your responses. To update -- I bought a box of Browning .22LR Hollow Point, 40 grain, 1435 velocity. My onageristic estimate is with its velocity, weight & expanded diameter it might compare in my Walther P22 with the .380 hardball as a carry piece ----->

 

"Onageristic"! I had to look that one up! LOL

 

SAAMI max pressure for the .22 LR is 24,000 CUP, well above most contemporary (late 1800s) centerfire pistols. Interestingly, the Mag has the same max pressure, apparently making use of increased case capacity at the same pressure to provide increased velocity. This strikes me as a relatively high pressure limit considering that the .22 LR and Mag cases are drawn from rather thin sheet metal. Every .22 rimfire chamber I have seen is fully supported with only a portion of the exposed rim facing downward in case of a rupture. As I recall, most manufacturers have chosen a lighter bullet weight to achieve the higher velocities, with CCI using a 3mm longer case with the shorter bullet in the Stinger. Again, newer propellants may also allow faster velocity of the original 40 Gr. bullet at the SAAMI spec pressure. "Hyper velocity" rimfire accuracy concerns run pretty much parallel to centerfire hot loads, in that it is rare to find a max load that produces excellent accuracy.

22 RF Short	-	21,000
22 RF Long & LR	-	24,000
22WRF	-	19,000
22WRM	-	24,000

 

The old white and blue box federal gold medal, said used by us Olympic team on the bricks. If you can find that I have never found better. The new federal gold medal version in the red box is nothing remotely like the old stuff. I benched a bunch of different 22's with both and it was night and day. That older stuff is my all time favorite and I don't even like to shoot what I have left because I don't want to run out lol. If you ever see that stuff I recommend buying it. Not sure off hand velocity but it's so consistent and seems to group amazing in anything and even works and cycles most autos without being super high velocity somehow. The new stuff won't even work in most of my semi's and is not even close to the older white and blue box. If you find it your lucky as I don't see it much anymore. I wish I bought a case when I bought my couple bricks about a year ago. An old guy had a couple cases he had for a couple years and decided to sell but I didn't know how good it was yet even though he told me I would never find better, I should have listened to the old timer.

 

After I read this post last evening, I was curious, so I looked up the SAAMI specs for .22 LR. SAAMI states max pressure for .22 LR as metric equivalent of 24,000 PSI for all configurations and commercially sold loadings of .22 LR. This specification does include .22 WMR loads as well. The specification includes higher velocity loads which are attained by the use of slower burning powders at the same peak pressure. I would guess that if you do the "Pi are round", surface area calculations that there is probably about a square inch of surface area on the case interior?

 

As to +P ammo, I think that the engineering limit has been reached in .22 LR. Strengthen the case for higher pressures and you also make the rim more resistant to firing pin strikes, as well as reducing internal capacity. Bullets and powder selection seem to be the only two variables left.