The Unofficially Official Sub-Caliber/“Micro Bore” thread!
- Thread starter Basher
- Start date
I'm currently working on two .10 Eichelberger Long Rifle builds. One barrel is a .10 caliber 16" long barrel blank (will have to be an SBR or pistol) and the other is a completely finished and ready to shoot barrel for a TC Contender. I had a custom die set made for necking down the .22LR primed brass. It's a pain in the ass, it's something like 12 steps and then bullet seating. The bullets are 7.2 grain solid copper that were each made one at a time on a Swiss Mill. Here's 2 photos with a .10ELR I made/loaded next to a factory .22LR. The photos don't really convey how stupidly small the .10ELR caliber actually is:
These are the muzzle ends of the .10ELR TC Contender barrel (left) and a Mk15 Mod 1 .50BMG barrel (right):
It might be funny to caption the barrel photo with "Finding herself" on the left and "Ready to settle down" on the right
These are the muzzle ends of the .10ELR TC Contender barrel (left) and a Mk15 Mod 1 .50BMG barrel (right):
It might be funny to caption the barrel photo with "Finding herself" on the left and "Ready to settle down" on the right
.22 Pokey
Don't have any of these, just like the photos.
Don't have any of these, just like the photos.
Man, those are cool.
I can’t believe I missed this thread! It was born when I was recovering from eye surgery, I guess.
I love the small calibers. For PDogs I shoot multiple .204, 17 Hornet, and subsonic 22LR for the up close and personal. All suppressed.
I own a CZ 22 Hornet in their euro Lux stock that is just so sweet.
I bought a used CZ 221 FB with beautifully figured wood. Had the thought I was going to enjoy the easier mag loading and bolt cycling vs. 17 Hornet, but I couldn’t find any extra mags!!!
Bought some CZ .222 mags as some said they’d work but I couldn’t get that to work well. Didn’t want to invest a ton of time modding the .222 mags, didn’t even know if it was possible, and sold it.
Pics I have on hand
Original Tikka T3 .204 (needs threading, haven’t shot it)
CZ 527 .204, has different scope now
Rem .204 in KRG W3 chassis and MKM experimental grips & magwell. Gotta trim those bolts that attach that Arca plate on the front. Bugs me.
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Wow, pleased to see some honest interest here!
Since I made this post, I’ve done almost nothing with any of my rifles. A few days after starting this thread, we found out I had significant blockages in one of my coronary arteries, so I had two stents placed mid-April. Then I got rear-ended in May, had gallbladder problems in July, and finally got that out late August, followed by a nasty reaction to a pain med for that, and finally an infected incision. It’s been one helluva shitty year…
I did recently accept a position to manage the local airport, so that’s kind of cool. Bit of a wild story, but it’s been HORRIBLY mismanaged since December of last year. I essentially got promoted from Asst. Manager to Manager on my first day (long story), and it’s a literal disaster here on so many levels, but I’m working very hard to get things fixed and running correctly.
One of my issues though is a coyote infestation. We see several a week that go where they want, when they want. They’re not scared of anything, and on an airport that’s a bit of a problem. We’re a bit rural here, so I touched base with the Airport Board Director and we’re going to verify the legalities of me taking them on the field. If I get the green light, the .17s may get the nod initially. I’ll see how they perform, and if they do OK I’ll use them as long as I can (until the yotes learn to stay farther away) to take advantage of the drastically reduced chance of a ricochet that the little .17s offer. Once they learn, I guess the .223 will have to come out.
Anyway, I’m slowly getting back in to things, and have stocked up on some IMR 4198 that came up locally at a good price. That should keep me shooting for quite some time. More to come as I get the ball rolling, but please keep sharing! I love seeing the oddball little cartridges like those above!
Since I made this post, I’ve done almost nothing with any of my rifles. A few days after starting this thread, we found out I had significant blockages in one of my coronary arteries, so I had two stents placed mid-April. Then I got rear-ended in May, had gallbladder problems in July, and finally got that out late August, followed by a nasty reaction to a pain med for that, and finally an infected incision. It’s been one helluva shitty year…
I did recently accept a position to manage the local airport, so that’s kind of cool. Bit of a wild story, but it’s been HORRIBLY mismanaged since December of last year. I essentially got promoted from Asst. Manager to Manager on my first day (long story), and it’s a literal disaster here on so many levels, but I’m working very hard to get things fixed and running correctly.
One of my issues though is a coyote infestation. We see several a week that go where they want, when they want. They’re not scared of anything, and on an airport that’s a bit of a problem. We’re a bit rural here, so I touched base with the Airport Board Director and we’re going to verify the legalities of me taking them on the field. If I get the green light, the .17s may get the nod initially. I’ll see how they perform, and if they do OK I’ll use them as long as I can (until the yotes learn to stay farther away) to take advantage of the drastically reduced chance of a ricochet that the little .17s offer. Once they learn, I guess the .223 will have to come out.
Anyway, I’m slowly getting back in to things, and have stocked up on some IMR 4198 that came up locally at a good price. That should keep me shooting for quite some time. More to come as I get the ball rolling, but please keep sharing! I love seeing the oddball little cartridges like those above!
Here's my 20-250 Impulse Predator after chopping 6 inches off the barrel.
Was shooting 55's at 4,200 with H4350.
Haven't chrono'd it after the chop, but it still shoots micro groups and is a lot easier to maneuver with now.
Was shooting 55's at 4,200 with H4350.
Haven't chrono'd it after the chop, but it still shoots micro groups and is a lot easier to maneuver with now.
I don't know how I missed this thread when it originated. I'm a big fan of the small calibers for shooting pdogs and even coyotes. My favorite is the 204 Ruger (have a couple of them) but I have 17 Rem, 20 VT, and 20 Practical also.
I am running 55's in my 20-250 chopped barrel to 18" getting 3450 fps running H4350.
4200 fps is impressive. How are you seating your bullets?
What primer you using?
Here’s my Tikka with a 22” 204 Muller 1:11 twist barrel on it. Shoots extremely well.
Not a micro/sub caliber, but it’s a small action rimmed cartridge…a 22 Hornet 
Lux 527 by CZ.
Lux 527 by CZ.
And an actual sub-caliber sister of the above, a 17 Hornet CZ 527 Varmint in a walnut Boyd’s stock. (Ignore the can koozie around the scope, that was a failed cheap lens hood idea that actually introduced more flare)
I haven't done much with this project, but I just purchased 3 more .10 caliber barrel blanks (I'll post photos when I have them in hand). That bring my total up to 4 of the the .10 caliber blanks (16", 18", 20", and 22"). These are probably the very last .10 caliber barrel blanks available anywhere. Not many people are messing with the .10 calibers, so I'm not sure if more .10 barrel blanks will ever be made in the future. I always grab the rarest parts first, and I'll start the actual builds later.I'm currently working on two .10 Eichelberger Long Rifle builds. One barrel is a .10 caliber 16" long barrel blank (will have to be an SBR or pistol) and the other is a completely finished and ready to shoot barrel for a TC Contender. I had a custom die set made for necking down the .22LR primed brass. It's a pain in the ass, it's something like 12 steps and then bullet seating. The bullets are 7.2 grain solid copper that were each made one at a time on a Swiss Mill. Here's 2 photos with a .10ELR I made/loaded next to a factory .22LR. The photos don't really convey how stupidly small the .10ELR caliber actually is:
These are the muzzle ends of the .10ELR TC Contender barrel (left) and a Mk15 Mod 1 .50BMG barrel (right):
It might be funny to caption the barrel photo with "Finding herself" on the left and "Ready to settle down" on the right
Does anyone else here shoot the smallest sub-calibers (.14, .12, or .10 calibers)? If so, please post some information and photos!
Very cool thread! I am still digesting everything. All of these are unfamiliar to me. Any of these be suitable for klipspringer, Dik Dik at 1-200 meters?
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