Thread: .22TCM Micro Varmint rifle build

look forward to your results as you get more trigger time . . . especially how far you can push those 40grn bullets out to on paper and critters.

ive had plenty of experience with 50, 55, 60 grain 224 bullets at +3000fps but the 40s are an unknown .. . good luck and good shooting

R.

@Micky Duck A proper thank you is in order.. I really appreciate the link to CCIs article on pistol primers in the .22 hornet...

Pistol primers for the win!!!

I loaded up 13 rounds with 12.8gr of 300MP, 40gr V-max and CCI small pistol primers and put them on paper at 100 yards.



There was a light wind from left to right but steady not gusting. I put 3 rounds on another target to test the load and the POI then put ten over the chrono and into this group:

The extreme spread was great! Id say these primers would sort out the other powders too but as clean as his 300MP burns I think Ill stay with it for now.

FPS= 3152, 3154, 3149, 3143, 3156, 3144, 3151, 3152, 3152, 3158 15fps ES



The two fliers puts the group just under an inch but thats still 8 shots inside 1/2 MOA! I cant wait to see what this little hot rod will do with bigger glass...

Made the most of the sunny day and had a play with the 16" .223 barrel on it too.


Even gave the old girl a few down the tube.. Brno 465 .22 hornet with 4X German Pecar optic
Not to shabby with crappy 45gr factory soft points but one day soon when I get time Ill work up a load for it with 35gr and 40gr V-max.







For those of you that didnt want to read through the whole article, here is the section regarding pistol primers in small cases:

Too Much Primer
You can have too much primer. When the output gas volume of the primer approaches that of the cartridge case, sometimes special handling is required. I remember when CCI was working with some experimental primers for 9mm Luger, and we started seeing odd time-pressure curves on the computer. Instead of the normal single peak, we saw two. One QA tech commented that it looked like the dual humps of a Bactrian camel.

It was a classic case of high gas volume but too little temperature. The primer's extra gas unseated the bullet while still trying to light off the main charge, producing one peak. Then the bullet retarded as it engaged the rifling, creating the second peak. Although a shooter would never notice this in a production firearm, that double hump was worrisome, and we abandoned that mix.

We have a classic case study in the .22 Hornet. For years Speer used Small Rifle primers in the Hornet. When I shot some of the data for Speer Reloading Manual Number 12, I found too many propellants that were so rangy they would not meet my standards for publishable loads. As a result, we did not show very many propellants for the Hornet, and the velocities were rather modest.

While I was developing the .22 Hornet 33-grain TNT HP bullet, I tried Small Pistol primers, knowing from the 9mm experience above that such a light bullet could be unseated by primer power alone. I'd talked to a number of handloaders who were getting better accuracy with Small Pistol primers, and I wanted a look at the concept in a lab setting. Sure enough, switching to Small Pistol primers reduced the variations in pressure and velocity and also reduced average pressure. The latter let us safely run the charge weights a little higher for velocities more appropriate to the Hornet. Manual Number 14 shows many more Hornet loads with better velocities, thanks to Small Pistol primers.

Well that goes in the "you learn something new every day" file.

awesome it was of help dude.enjoy your new rifle ,you sure are putting in the hard yards to make her tick.

I got it to the stage where it shoots 40gr great at 3150fps but curiosity got the best of me this morning.
The .22 TCM reamer I ordered just had the std length free bore for the pistol cambering so the 40gr bullets had to be seated very deep to clear the lands.
I decided to push the throat forward to pull the projectiles out longer. This will give less case pressure and possibly allow for hotter loads without compressing loads.
I also wanted to try some 50gr V-Max through it so it had to be done.



I set the barrel back up in the lathe and made up a vmax dummy round of 39.5mm COAL which was a happy medium of getting the 40gr V-max boat tail off the powder and up into the neck to shoulder junction and the 40gr flat base Blitzking with still at least 3/4 of the neck engaged.
This meant pushing the lands forward 178 thou.



Interestingly it didnt lose any velocity shooting my same V-Max load I tested yesterday only seated further out but the primers did show much less pressure.
Out of curiosity I moved up the charge gradually 0.2gr at a time until I got to a flat primer that looked like my last max load of 13gr of 300MP.
At 13.8gr of 300MP and my longer seated 40gr Vmax it gave me a scorching 3435fps!

Id say a load at 3300fps would be better on brass life so I will have to do some more grouping tests at that speed when I get a chance.



I also worked up some 50gr V-Max loads with the slightly slower burning 2205, ADI data shows 11gr of 2205 gave 2500fps with a 50gr in a 24" barrelled .22 hornet so I figured that was a good place to start.
11.0gr of 2205 gave me 2585fps and no pressure signs so I kept bumping up until I got to a full case at 12.0gr (but no longer a compressed load). This gave mild pressure creators at 2708fps.
Ill load a few of those to try on paper too.

It is threads like this one of yours that make this forum valuable.
Very interesting thank you.

Originally Posted by Wingman

Not really a worry but a annoyance meaning annealing before every load.
Personally if I was to bother neck turning and having to have a custom chamber reamer made to suit the new neck dia, Id be looking at making it .20cal and 40deg improved at the same time. That would be the perfect calibre in this little hot rod, the same weight bullets only faster with a higher BC.

This would be a very cool round as a 20 Cal. Not sure I'd go with a 40 degree shoulder just for feeding considerations, maybe 30 degrees and shorten 20 Tactical dies? I have thought about doing a 20 Vartarg but this could be a better option. I have a 20 Tactical reamer and a barrel on the way for it

Originally Posted by The Claw

This would be a very cool round as a 20 Cal. Not sure I'd go with a 40 degree shoulder just for feeding considerations, maybe 30 degrees and shorten 20 Tactical dies? I have thought about doing a 20 Vartarg but this could be a better option. I have a 20 Tactical reamer and a barrel on the way for it

Here it is in .20cal



I agree that would be a great cal but a bit more faffing around with neck turning and fire forming etc.

Your best bet would be to have a custom reamer made and just open up the top of some Redding .22 TCM dies for a .20cal neck sizing collet.
The case wouldnt fit into any cut down dies as it is the bottom of a .223 rem case so much wider than the top section.


Edit: just found a forum where someone has made one

http://www.saubier.com/forum/showthread.php?t=27048

This is cool Wingman i thought 221 fireball be wicked but 22tcm looks cooler 😎👍

I suppose I should also mention there's a .17 TCM wildcat

17 tcm wildcat...by the time load is worked out and scope zeroed the bore is half way through usefull life/shot count????????? LOL

Originally Posted by Micky Duck

17 tcm wildcat...by the time load is worked out and scope zeroed the bore is half way through usefull life/shot count????????? LOL

The barrel life will be many thousand rounds, so unless you are spectacularly poor at load development and sighting in then barrel life shouldn't be a problem!

It’s only burning 11-13gr of powder so barrel heating/firecracking in the throat won't be a big problem like with big capacity overbore rounds

Sent from my SM-N950F using Tapatalk

Originally Posted by Micky Duck

17 tcm wildcat...by the time load is worked out and scope zeroed the bore is half way through usefull life/shot count????????? LOL

Youd be surprised.. reports are of very low barrel heat, I can tell you first from my .22 TCM that this is the case. Even firing 20 or 30 rounds in quick chrono sessions the barrel is barely warm to the touch. The suppressor has yet to get hot.
Other than general bore wear from friction I dont think throat flame erosion will be an issue in the TCM.
Id say the 17 TCM will run parallels with the .17 hornet much like the .22TCM does with 22 hornet.

shouldve gone fishing this morning.just knew you fellas would bite at that one LOL.
years back I remember reading an article on .17 wildcats (back before they were normal and decent barrels were being made) craziest one I read of was a .17/06 guy shot all manner of beasties with it...highly un efficent .

While .17 cals have never been my thing and Id be the last guy to defend their performance, you did prompt me to document the lack of barrel heat I had noted in my TCM that Id forgotten to mention..
The round count in my Shilen is now 80 rounds and I have two very good loads sorted also tested 5 powders 4 bullets and 4 primers. (not all of which I documented)
While that is at the higher end of "normal" round count for developing a load, bare in mind there is very little info out there in regards to shooting this pistol round in a rifle with varmint projectiles.
This was always going to be a experimental toy for me and now I have good reliable safe loads that cycle reliably, Ill continue to dabble with heavier projectiles etc while putting it to use on the bunnies in my spare time.
Hopefully this write up will save others who load this cal a lot of time and resources setting up their own TCM rifle.