X22LR Max-11A1/15 Prototypes

[strobro32]

Here is the progress with the experimental 22LR prototype made with the guts of a S&W 15-22. The CMMG 22LR kit conversion is on Post #11.

Spacer, bolt assembly, barrel with Cry havoc quick change barrel

Spacer, bolt assembly w/ sear catch plate, barrel with Cry Havoc quick change barrel

1.0 test 2200 RPM

https://flic.kr/p/2obmiXZ

1.2 test 1850 RPM

https://flic.kr/p/2odVbdH

2.0 test 1000 RPM

https://flic.kr/p/2ofmEL1

 

[strobro32]

I thinking about raising the ROF up to 1200 RPM to help with ejection. The open bolt 10/22 Krinker Plinker runs at 1425 RPM and the GSG 522 runs at close to 2K RPM.

 

[Deerhurst]

That's very simple. Good work!

Wonder if I could adapt a CMMG style mechanism into the Max10/15 with a custom housing/carrier.

 

[LawBob]

That's very simple. Good work!

Wonder if I could adapt a CMMG style mechanism into the Max10/15 with a custom housing/carrier.

Someone thought not due to ejection issue?

 

[strobro32]

I kinda wanta try to convert a CMMG kit now.

 

[LawBob]

I kinda wanta try to convert a CMMG kit now.

Ok. I’ll test fire it for you.

 

[Tinman45]

I badly need something like this in my life.

 

[strobro32]

I converted and tested open bolt CMMG kit today. It ran at 1392 RPM. I had a 5 rounds fail to feed out of the 25 round CMMG mag. I'll need to work on that. I'm going to order a 6 lb mainspring this week. The OEM CMMG 22lr mainspring seems a little underpowered for the open bolt.

 

[strobro32]

I was suspecting the CMMG 22LR mag was not feeding at the proper angel so I just tried a S&W 15-22 mag with the Deerhurst clip. It ran great with 23 rds well. There was not a single ejection issue. The first 2 rounds in the mag were failures to fire but they entered the chamber just fine. I think the 6 lb mainspring will fix that. The ROF fire was 1800 RPM.

 

[theduke]

Have you given thought to the 261 mag/conversion?

Or mix and match the 3 different mags to the 3 different internals.

I'm sure you have but curious on the thoughts in your Noodle.

Clearly your way ahead of most generic thinking here.

 

[strobro32]

Here is the video from testing the CMMG kit this morning. I had problems with the CMMG mags but the S&W 15-22 mags and the Dearhurst clips ran really well, not a single ejection issue. I will order the 6 lb mainspring this week for more testing next week. It was much cheaper and faster to convert than the S&W 15-22 version. The CMMG 22LR kit a fun little sucker. ROF AVG was 1722 RPM. I really enjoy this combo.

https://flic.kr/p/2ogwNDH

Edit:
Ammo tested in the video was CCI Mini Mag 40 Gr RN.

I also tried CCI Standard Velocity 40gr RN = ROF 1612 RPM.
CCI Stingers
Rem Golden Bullets
Wolf Extra Match
Blazer

It worked with all ammo I tested and the subsonic ammo had lower ROF. I will need to get numbers next week.

 

[pjm204]

Would you be willing to share what is required to convert the CMMG kit? It would be pretty awesome to be able to spend $169 for a cmmg kit and not have to change out the barrel to run it. Also, any thoughts on how to slow it down, 750-1000 would be more appealing to me. Either way, awesome work!

 

[strobro32]

I will explore slowing the CMMG 22LR kit but it does not look promising without heavy modification.
The OEM CMMG 22LR kit with the M16 runs on average between 1100-1200 RPM.

I already have plans in my noodle for a closed bolt design. It might slow it down and would require no mods to the CMMG kit.

1. Weld a blob on the bolt face.
2. Carve blob into fixed firing pin, a job for a machinist, dentist, jeweler or miniature sculptor.
3. Create sear catch plate.
4. Attach sear catch plate to bolt.
5. Mill/file inverted wedge into front of main spring housing, this is necessary or the Lage bolt charging handle extension can jam the bolt.
6. Mill/file inverted wedge shape on Lage bolt charging handle extension.
7. Create kit spacer, 3.5" x 1" OD wood dowel to push the kit forward for the M11A1, 5.5"x1" OD dowel for the Max-11/15.
8.**Probably add 6 lb main spring- not tested yet.

I also would include a Cry Havic quick detach barrel system for all barrels.

 

[pjm204]

1. Weld a blob on the bolt face.
2. Carve blob into fixed firing pin.
3. Create sear catch plate.
4. Attach sear catch plate on bolt.
5. Mill/file inverted wedge into front of main spring housing
6. Mill/file inverted wedge shape on Lage bolt charging handle extension.
7. Create kit spacer
8.**Probably add 6 lb main spring

**not tested yet

I also would include a Cry Havic quick detach barrel system for all barrels.

Awesome, thanks! Any chance of getting a few pictures?

Would it be possible to simply fix the stock firing pin on the bolt forward versus welding a fixed firing pin? I do have a TIG welder so I suppose I could do either.

Would this work with the stock lage setup without purchasing the quick detach barrel system? (Forgive my stupid question, I've never owned the CMMG kit)

 

[LawBob]

For 1-2 couldn’t you take firing pin spring out and perhaps just weld it forward from the rear?

 

[strobro32]

No. the case will not slide up under a top mounted fixed firing pin..

 

[strobro32]

Would this work with the stock lage setup without purchasing the quick detach barrel system? (Forgive my stupid question, I've never owned the CMMG kit)

Yes but you would not want to. 22LR is very dirty and you do not want lead in an adjustable gas block, even if the adjustment screw is closed. I imagine it would weld the screw closed. I think a CMMG dedicated 22LR barreln is a better option. I imagine Richaerd would be frustrated by the number of clogged gas blocks that show up as his shop. It's probably better to buy the Lage upper vice blocks, wrench tool and change barrels for 22LR or a QDB system.

Pictures will come when the process is refined. I've only had 24 hours with the kit to create proof of concept.

 

[LawBob]

Awesome, thanks! Any chance of getting a few pictures?

Would it be possible to simply fix the stock firing pin on the bolt forward versus welding a fixed firing pin? I do have a TIG welder so I suppose I could do either.

Would this work with the stock lage setup without purchasing the quick detach barrel system? (Forgive my stupid question, I've never owned the CMMG kit)

22 is dirty. With the cmmg chamber sleeve you’d be putting dirty 22 into the gas system as well. The barrel twist rate is also 1:7 not a normal 1:10-12 for a 22

But I’m like you. I’d prob use the 556 barrel and get the kit with the chamber sleeve.

Prob recommend a 1/2 mag dump of 556 immediately after to burn it out.

Can the adj gas block be closed fully?

 

[LawBob]

Yes.

Pictures will come when the process is refined. I've only had 24 hours with the kit to create proof of concept.

Thanks for giving me something else to desire. Appreciate it.

 

[LawBob]

No. the case will not slide up under a top mounted fixed firing pin..

Ah. That was the feeding issue discussed elsewhere.