Shooting the AR15 22LR Conversion Kits

[TD1886]

Noting almost [at least I've not found any other twists] all dedicated AR 22LR uppers and replacement barrels have 14 or 16" twists. Hard to find any groove specifications for those barrels but I'm assuming they are the standard .222/.223 of regular 22LR barrels. You may have something on the barrel groove diameter affecting accuracy but the bullets in the video targets all went through point first demonstrating the bullets were sufficiently stabilized.

My previous testing Back in the early 'mid/late 80s using multiple military M16As (12" twist), M16A2s (7" twists) and commercial AR HBars (9" twist) showed definitely the 12" twists always gave better accuracy. That's why back in '06 when I found a new military contract refinished M16 upper with a new milpsec made M16A1 barrel I bought it immediately and built my AR "shooter" for use with M193 and Speer 52 gr HP reloads along with the usefulness of the M261 device.

The shooter in the video states at the end of the video that the Ruger barrel is a 16" factory barrel with an 8" twist. I must not have had my "ears" in when I first watched it and "heard" custom and assumed it was as I didn't know Ruger was useing 8" twist barrels as they are mostly used for competition rifles. Not on 16" M4 wanna be's. He also wonders if the inaccuracy, particularly with the higher velocity loads, has something to do with the fast twist. He's right, it does.

Well I'm going to try find out if he was right. I got some tricks to try. I think his CMMG unit may have been a little more accurate if it fit tighter or maybe if it that buffer spacer which keeps it pressed forward tighter. That may or may not stopped the gas blow back in the charging handle channel as the shoulder of the adapter would be pressed more to keep it's datum line up against the datum line of the chamber for a better gas seal.

[Outpost75]

Limited experience with M261 here. My reserve unit in 1980s had a dozen by Saco Defense which armorers mated up with older M16A1 uppers with 12" twist barrels. They shot acceptably for training purposes indoors at 25 yards with the Winchester white box ammo being issued. I had an opportunity to buy one, but firing outdoors at 100 yards with my 9" twist CMG2 barrel on Colt HBAR I was not impressed and passed.

[barnetmill]

I understand why the AR15 22LR Conversion Kits came about for military usage and early AR 15 civilian usage. In the 80's and early 90's I had to qualify with them. I didn't care for them then and I still don't care for them now.

I did liberate 3 AF M-261's when the AF discontinued usage. I have mine paired with 3 retro builds I did but I rarely shoot they. I do have several dedicated 22 LR uppers that I love. I built a couple of Krieger barreled dedicated 22LR uppers that will give the best match rifles for the money.

What I don't understand is why folks spend $169 or more on a conversion kit when you can purchase a dedicated 22 LR upper for around $50 more?

https://www.bearcreekarsenal.com/22-...l-branded.html

my reason for the conversion is the trigger and sighting arrangement are identical since an AR pistol more of closer range combat weapon. 100 ft is my max .22 training range for now. If I want shoot further I will have to use 5.56.
Since it being used with rimfire full strength springs are required for the trigger - hammer group. Buy a dedicated upper and you need a new optic. The ATF forbids iron sights or fixed focus scopes on AR pistols.

[TD1886]

my reason for the conversion is the trigger and sighting arrangement are identical since an AR pistol more of closer range combat weapon. 100 ft is my max .22 training range for now. If I want shoot further I will have to use 5.56.
Since it being used with rimfire full strength springs are required for the trigger - hammer group. Buy a dedicated upper and you need a new optic. The ATF forbids iron sights or fixed focus scopes on AR pistols.

Good post

[M-Tecs]

my reason for the conversion is the trigger and sighting arrangement are identical since an AR pistol more of closer range combat weapon. 100 ft is my max .22 training range for now. If I want shoot further I will have to use 5.56.
Since it being used with rimfire full strength springs are required for the trigger - hammer group. Buy a dedicated upper and you need a new optic. The ATF forbids iron sights or fixed focus scopes on AR pistols.

????????????????????????

https://www.guns.com/firearms/handgu...l-new?p=866896

https://www.impactguns.com/semi-auto...57894-81000403

https://www.deltateamtactical.com/jo...te-pistol.html

https://palmettostatearmory.com/psa-...romeo-msr.html

https://palmettostatearmory.com/psa-...istol-kit.html

https://palmettostatearmory.com/psa-...654489732.html

https://moriartiarmaments.com/pistol...t-air-clear-10

https://www.impactguns.com/Semi-Auto...2792-HG2797-N/

Pistols with a brace using a sighting system that requires shouldering the brace to use did/does change the classification to a SBR since that show intent to shoulder per the ATF.

As to the ATF forbidding iron sights or fixed focus scopes on AR pistols please site your source? Seems place like lots of manufactures/retailers are breaking the law?????

[TD1886]

????????????????????????

https://www.guns.com/firearms/handgu...l-new?p=866896

https://www.impactguns.com/semi-auto...57894-81000403

https://www.deltateamtactical.com/jo...te-pistol.html

https://palmettostatearmory.com/psa-...romeo-msr.html

https://palmettostatearmory.com/psa-...istol-kit.html

https://palmettostatearmory.com/psa-...654489732.html

https://moriartiarmaments.com/pistol...t-air-clear-10

https://www.impactguns.com/Semi-Auto...2792-HG2797-N/

Pistols with a brace using a sighting system that requires shouldering the brace to use did/does change the classification to a SBR since that show intent to shoulder per the ATF.

As to the ATF forbidding iron sights or fixed focus scopes on AR pistols please site your source? Seems place like lots of manufactures/retailers are breaking the law?????

From the way I understand it if you mount a scope on an AR pistol that is a "rifle scope" which is determined by: (iii) whether the weapon is equipped with sights or a scope with eye relief that require the weapon to be fired from the
shoulder in order to be used as designed;

Here's the link:

https://www.atf.gov/rules-and-regula...08pdf/download

I believe doing this in the beginning is where they (the manufacturers) got into trouble with the SBR/AR Pistols. If if you don't put a shouldering device on it, it's the "intent" that makes it illegal.

[M-Tecs]

From the way I understand it if you mount a scope on an AR pistol that is a "rifle scope" which is determined by: (iii) whether the weapon is equipped with sights or a scope with eye relief that require the weapon to be fired from the
shoulder in order to be used as designed;

Here's the link:

https://www.atf.gov/rules-and-regula...08pdf/download

I believe doing this in the beginning is where they (the manufacturers) got into trouble with the SBR/AR Pistols. If if you don't put a shouldering device on it, it's the "intent" that makes it illegal.

That is my understanding also and that is 180% opposite of the claim that "The ATF forbids iron sights or fixed focus scopes on AR pistols".

[TD1886]

That is my understanding also and that is 180% opposite of the claim that "The ATF forbids iron sights or fixed focus scopes on AR pistols".

I agree the iron sights is incorrect. Let's clear up what you or they mean by a fixed scope. All I'll say is that if a scope is a rifle scope by very short eye relief whether is a fixed power or variable is in violation.

It my opinion that the ATF (and whoever else is in all this that are anti gun) deliberatly made it all confusing to trip us up.

[M-Tecs]

I agree the iron sights is incorrect. Let's clear up what you or they mean by a fixed scope. All I'll say is that if a scope is a rifle scope by very short eye relief whether is a fixed power or variable is in violation.

It my opinion that the ATF (and whoever else is in all this that are anti gun) deliberatly made it all confusing to trip us up.

Per the ATF

(iii) whether the weapon is equipped with sights or a scope with eye
relief that require the weapon to be fired from the shoulder in
order to be used as designed;
 Sights or scopes that cannot be used without shouldering the
weapon indicates that the firearm is designed and intended to be
fired from the shoulder

[TD1886]

Per the ATF

(iii) whether the weapon is equipped with sights or a scope with eye
relief that require the weapon to be fired from the shoulder in
order to be used as designed;
 Sights or scopes that cannot be used without shouldering the
weapon indicates that the firearm is designed and intended to be
fired from the shoulder

Well of courser per the ATF. They think then can legislate laws and inact them.

[M-Tecs]

From the way I understand it if you mount a scope on an AR pistol that is a "rifle scope" which is determined by: (iii) whether the weapon is equipped with sights or a scope with eye relief that require the weapon to be fired from the
shoulder in order to be used as designed;

Here's the link:

https://www.atf.gov/rules-and-regula...08pdf/download

I believe doing this in the beginning is where they (the manufacturers) got into trouble with the SBR/AR Pistols. If if you don't put a shouldering device on it, it's the "intent" that makes it illegal.

You can put what eye-relief scope you want on any handgun as long as it DOES NOT have a brace. That is where the "intent" comes in. Can't have "intent" to shoot it from the shoulder if it cannot be fired from the shoulder. The long range handgunners do it all the time on their single shot and bolt action handguns and its 100% legal.

[Digital Dan]

Larry Gibson's comments about bullet diameter very early in this discussion sparked a little curiosity and I just measured a few from my stockpile.

CCI .22 CB Short, vintage 2000-2010 = .225"
Wolf MT and SK Standard +, vintage 2015-2020 = .223"
Remington .22 Long, vintage estimated at 1980-1990 = .222"
WW .22 Short, vintage estimated at 1980-1990 = .222"
WW PP .22 LR, vintage 2000 = .223"

I shoot the CB Shorts in a Contender Carbine w/match chamber and it shoots 5 shot one-hole groups at 25 yards

WW PP are used in a 10/22 manufactured in 1971 w/full length bedding. One hole groups of 5 at 50 yards, and one group of three fired at 100 yards of .436". It is my preferred ammo for the 10/22.

Wolf MT/SK is fired in a variety of rifles and is in fact my go to round for all. T/C Carbine (match barrel), Rem 513 S&T etc. All shoot the ammo quite well. My best 50 yard group with Contender was .091".

[TD1886]

Larry Gibson's comments about bullet diameter very early in this discussion sparked a little curiosity and I just measured a few from my stockpile.

CCI .22 CB Short, vintage 2000-2010 = .225"
Wolf MT and SK Standard +, vintage 2015-2020 = .223"
Remington .22 Long, vintage estimated at 1980-1990 = .222"
WW .22 Short, vintage estimated at 1980-1990 = .222"
WW PP .22 LR, vintage 2000 = .223"

I shoot the CB Shorts in a Contender Carbine w/match chamber and it shoots 5 shot one-hole groups at 25 yards

WW PP are used in a 10/22 manufactured in 1971 w/full length bedding. One groups of 5 at 50 yards, and one group of three fired at 100 yards of .436". It is my preferred ammo for the 10/22.

Wolf MT/SK is fired in a variety of rifles and is in fact my go to round for all. T/C Carbine (match barrel), Rem 513 S&T etc. All shoot the ammo quite well. My best 50 yard group with Contender was .091".

If you go back and look I mentioned the diameter of the 22lr bullet first and in fact the reason I started this thread with Larry Gibson. Here's one line from that first post: " What is your opinion that destroys the accuracy in the 7 twist, the incompadible diameter of the 22LR bullet to the .224 groove, the rpm of the bullet, or the fast twist is somehow ruining the very soft bullet to cause it be inaccurate." It has to be one of the reason of the inaccuracy.

[Digital Dan]

https://saami.org/wp-content/uploads...2018-06-13.pdf

Scroll down about 14 pages or so.

[TD1886]

You can put what eye-relief scope you want on any handgun as long as it DOES NOT have a brace. That is where the "intent" comes in. Can't have "intent" to shoot it from the shoulder if it cannot be fired from the shoulder. The long range handgunners do it all the time on their single shot and bolt action handguns and its 100% legal.

You'll see I mentioned that in what you quoted, that is with the brace. What got the manufacturer in trouble is they submitted the that firearm without a scope to the ATF. The ATF approved it. After it was approved the company put advertisements out with the approved firearm with a "rifle scope" and that's when the poop hit the fan with the ATF. A friend of mine involved this this said that if the company would have submitted the firearm with a rifle scope on it the story would have been different. We both think the ATF wouldn't have approved it. It is my believe that the "brace" was first intended to help steady the firearm. Then the ATF started complaining. Then some smart people on the side of the braces came up with it was meant for handicapped people. Known fact when some legal procedure involves handicapped people the law kind of favors them.

Maybe we can start a new thread on this as it would be nice to stick to the topic of this thread which is the 22lr conversion units for the AR15. Notice, so you don't get twisted in a knot, that I'm not telling you or anyone else what to do as we've had that discussion before, okay?

[Larry Gibson]

To add to Digital Dan's list (post #52);

Measured some unswaged 22LR bullets this morning with a micrometer. I noticed a large number of the cartridges were not symmetrical round giving a variation of up to .0015 in measurement of the same bullet. Of course lot to lot variation in bullet diameter will probably occur.

Lapua Midas+ .2245
Win Pistol Match .2225
CCI CB Longs .2235
Fed Amer Eagle .2245*
Fed Champion .223- 2253
CCI Blazer .2235
Win Match .2245
CCI Target .224
Rem Golden .224*
CCI MiniMag .2225*
CCI Velocitor .223
Armscorp HV HP .224*
CCI Stinger .2245
Wolf Match Target .224
CCI Segmented .224
CCI Subsonic 45 HP .2255

“*” are those I swaged to .225 with the Waltz die and primarily use in the 12” twist AR w/M261 device. I also use the Winchester HV HP copper plated bulk but did not have any unswaged to measure.

[Larry Gibson]

If you go back and look I mentioned the diameter of the 22lr bullet first and in fact the reason I started this thread with Larry Gibson. Here's one line from that first post: " What is your opinion that destroys the accuracy in the 7 twist, the incompadible diameter of the 22LR bullet to the .224 groove, the rpm of the bullet, or the fast twist is somehow ruining the very soft bullet to cause it be inaccurate." It has to be one of the reason of the inaccuracy.

As I've mentioned several times, with my previous testing of various AR/M16s with common .23/5.56 barrels with .224 groove of 7, 9 and 12" twist the inaccuracy of the faster twist barrels is caused by the faster RPMs greater centrafugal force on the bullets. Also, the bullets may be getting damaged more by the sharper leade angles of the faster twist. If the bullets are damaged more [you would have to trap some out of each twist to know for sure] but suffice to say any damage that unbalances the bullet would give the increased centrifugal force of the faster twist [because they have higher RPM given the same velocity] more to act on.

It may be a combination of all three reasons. However, swaging the bullets to a uniform .225 should negate the .224 barrel reason. Remains to be seen though through additional testing.

[TD1886]

As I've mentioned several times, with my previous testing of various AR/M16s with common .23/5.56 barrels with .224 groove of 7, 9 and 12" twist the inaccuracy of the faster twist barrels is caused by the faster RPMs greater centrafugal force on the bullets. Also, the bullets may be getting damaged more by the sharper leade angles of the faster twist. If the bullets are damaged more [you would have to trap some out of each twist to know for sure] but suffice to say any damage that unbalances the bullet would give the increased centrifugal force of the faster twist [because they have higher RPM given the same velocity] more to act on.

It may be a combination of all three reasons. However, swaging the bullets to a uniform .225 should negate the .224 barrel reason. Remains to be seen though through additional testing.

That's exactly what I intend to do Larry is swage the bullets. When you did that did you notice any increase at all in accuracy? What I'm going to do is with the unit out of the rifle I'm going to keep swaging up the diameter until I reach the maximum that will fit the chamber. I may even swage far enough up to where I have to hand insert them. I definitely want to see what a fatter bullet will do.

[Larry Gibson]

"That's exactly what I intend to do Larry is swage the bullets. When you did that did you notice any increase at all in accuracy?"

Never actually tested the difference. When I got the M261 device back in '06 I already had the Paco and Litz dies so I just arbitrarily swaged the rounds to uniform them at .225 and to improve the HP opening for greater lethality. I shot a few them in my 9" twist Colt HBar but not many as I really was looking for a 12" twist M16A1 barrel. Wasn't until '08 I got found the 12" twist M16 upper with the new milspec M16A1 barrel. As mentioned, I have just arbitrarily swaged the 22LR ammo for it.

Previous shooting back in the early '90s with M16A1s, M16A2s and HBars had been done at 50' and 50 yards with out of the box 22LR ammo.

I'll be testing some different ammo makes/types both swaged and out of the box as soon as it cools a bit.

[TD1886]

"That's exactly what I intend to do Larry is swage the bullets. When you did that did you notice any increase at all in accuracy?"

Never actually tested the difference. When I got the M261 device back in '06 I already had the Paco and Litz dies so I just arbitrarily swaged the rounds to uniform them at .225 and to improve the HP opening for greater lethality. I shot a few them in my 9" twist Colt HBar but not many as I really was looking for a 12" twist M16A1 barrel. Wasn't until '08 I got found the 12" twist M16 upper with the new milspec M16A1 barrel. As mentioned, I have just arbitrarily swaged the 22LR ammo for it.

Previous shooting back in the early '90s with M16A1s, M16A2s and HBars had been done at 50' and 50 yards with out of the box 22LR ammo.

I'll be testing some different ammo makes/types both swaged and out of the box as soon as it cools a bit.

Okay thanks Larry. I'll do the testing, if I can, and we will see what the difference is. BTW it's going to be an early COLT unit which is very close to the M261, definitely not the CMMG. I wouldn't have the CMMG. Stay tuned the unit arrives next week sometime and then I have to get to it when I have time.

Pretty good thread so far don't you think?