DIY conversion from pistol to carbine

Range report........

I only tested it with my PF940c. I was getting failures to feed with a KCI 33rd mag that I use for range work. That mag has never given me a problem before. I used two other factory glock mags (15rds w/extensions to 22rds) and they ran flawlessly through multiple loadings.

I forgot my tripod, so I couldn't get serious about evaluating group size. Shooting offhand at 25 yards I was getting palm sized groups firing with a 0.5 second cadence. Today was primarily for function checking and I'm pretty stoked with how it went.

The rear stabilizing rod worked well and didn't make it uncomfortable to grip the unit (that's what she said). Looking forward to testing this with the PF45 and to checking groups with the bipod.
 
Forgot to mention.......

I am surprised you don't find any side-to-side frame distortion, since there is still little lateral support,
I didn't see any signs of this, but maybe that's why the KCI mag was having issues. I think lateral/horizontal flex is less likely because the torque of the shooters grip is vertical and that also directs the torque of recoil vertically.

I'm going back to the range tomorrow with the bipod and some 33rd factory Glock mags. I'll post another follow-up and some pictures of target groups.
 
Tested for groups at the range today......

(Excuse Alert!!!)
I realized that my pistol range really isn't set up for bench shooting (see pic below). The stools are too short for the "bench" and the bench is too narrow to really spread out for appropriate bench marksmanship. I managed to get a pretty stable rest and this is what I got at 50 yards. Next time I will take it to the rifle range that has a better bench setup.
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Excluding the flyer in the 5-shot group, it came out to 5 MOA. At 50 yards, my red dot totally obscures the center bullseye, so that is what I was shooting for.

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The 33-round factory Glock mags were reliable, but so was the KCI mag today. I had a couple of failures to return to battery and a couple of failures to reset the trigger. I went through a 33-round mag at 25 yards and noticed that when I was shooting more rapidly off-hand and concentrating less, I had no malfunctions (hand-sized group). With the next 33-round mag, I clamped down for maximum accuracy and had a few malfunctions. It seems like you can still over-torque this thing. I'm looking forward to taking it up to my spot in the mountains where I can rapid-fire and shoot steel on the move. I think that's a better test of a PDW/PCC. I'll post more when I have more data.
 
Well, I found a way to get rid of ALL of the frame flex...........


Use a 1911.

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Yeah, it's a bit ridiculous, but it keeps me out of the strip clubs. Hopefully getting to the range this weekend for testing. More to come later.
 
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GOD!!! I LOVE AMERICA!!!!!


Ps- strip clubs aint so bad. Also girlfriends or whatever. Not so bad.
Juuusssstt saying
 
Well, I found a way to get rid of ALL of the frame flex...........


Use a 1911.

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Yeah, it's a bit ridiculous, but it keeps me out of the strip clubs. Hopefully getting to the range this weekend for testing. More to come later.
Where’d you get the parts for that rig ? Can you provide links ? Does it work for any type pistol. I shoot 911, 357 or 40 in an MCK cuz of nerve damage. This looks very rifleish (is that a word 😂) would like to check it out….DIY is right up my alley 🔨 🔧 🪛🪚🪓🩹📐🍕
 
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Where’d you get the parts for that rig ?
Except for th 16" barrel, minimalist stock, and optics, it's all stuff from Amazon. I used 1" and 30mm (outside diameter) carbon fiber tubing, scope rings and ringed pic rails that are usually used for piggybacking red dots on scopes. I'll put a list of links together and post them tomorrow.
 
Where’d you get the parts for that rig ?
Does it work for any type pistol

It will theoretically work with any pistol that has a pic-rail, but there are a couple of caveats...

1. If there isn't a 16" barrel available for the pistol you want to use, you will be in SBR territory in the eyes of the ATF.

2. As noted in prior posts (before the 1911 post), polymer-framed pistols require a rod for frame-flex mitigation if you want any kind of accuracy/reliability and to avoid over-stressing your frame.

Links...
Pistol scope mount
Carbon fiber tubing 30mm & 1"
Scope rings: 30mm & 1"
tube-to-picatinny
Grip-pod
16" 1911 barrel
minimalist stock
------- for a polymer set-up--------
16" Glock barrels
Carbon fiber seat post for flex-mitigation rod
Vertical grip/Glock mag holder
 
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Range Report
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"Houston, we have a problem."
I took the rig to the range. I didn't use the scope in the above photos. Instead, I mounted an inexpensive Sig Romeo5 red dot to keep things simple. The theme of the morning was "wandering POI". The Romeo5 was mounted securely and has held zero with other rifles, so it wasn't the problem. The problem is likely due to the optic mount itself.

Even though it mounts very solidly to the pistol's pic-rail, the optic mount must be flexing just enough to affect the POI. I was able to shift the POI based on how solidly I gripped the unit and pulled it into my shoulder. The overall unit is very sturdy and I'm pleased with the "feel" of it while shooting, but the wandering POI is a deal killer.

I actually got much better groups when I was using the unit designed for polymer pistols (see way above in early posts) because they have their optic mounted on the slide - independent of the attachment point for the stock/brace system. With the 1911 setup, the pistol's optic mount is the common attachment point for both the optic and the stock/brace system.

One potential solution is to cut away the back half of the optic mount's attachment point to the pistol's pic-rail. This will allow the stock system to attach directly to the back half of the pistol's pic-rail and avoid contact with (and influence on) the optic. The section in red below doesn't contain the mounting screw but does sit in the pic-rail's lateral cuts and has a clamping effect when the forward screw is tightened.

(This is a stock photo from Amazon and obviously not a 1911, but you get the idea.)
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My concern with cutting this section away is the effect that it may have on the stability of the optic mount itself. Guess I won't know until I try it. Now let's see If I can cut it away and not have it look "ghetto", but ultimately, as I said above, the whole thing is a bit ridiculous anyway. I'll post a follow-up picture when it's done and then again after testing.
 
Love the Rube Goldberg vibe you have going on with this rig. Major style points.

I think you are going to be limited in accuracy regardless on how you mount the optic on the pistol. You just can't overcome the momentum of having that much barrel hanging out there in front of the bushing. Though, I can think of one way... mount an RMR on the barrel instead of the pistol frame.
 
I think you are going to be limited in accuracy regardless on how you mount the optic on the pistol. You just can't overcome the momentum of having that much barrel hanging out there in front of the bushing. Though, I can think of one way... mount an RMR on the barrel instead of the pistol frame.
True (limited in accuracy regardless), but I was hoping I could be more accurate with it than I am shooting the pistol in a standard fashion, otherwise, why bother? My Glock with the long barrel did fairly well (see 50-yard group way up in the thread - minute of man). When you said "mount an RMR on the barrel", did you mean on the slide (milled or with a rear sight RMR plate) or did you mean a clamped-on rail on the barrel? A barrel-clamped pic-rail with a red dot mounted to it would definitely have the Rube Golberg vibe!
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This would take my mall-ninja creation to a whole new level.:ninja:
 
True (limited in accuracy regardless), but I was hoping I could be more accurate with it than I am shooting the pistol in a standard fashion, otherwise, why bother? My Glock with the long barrel did fairly well (see 50-yard group way up in the thread - minute of man). When you said "mount an RMR on the barrel", did you mean on the slide (milled or with a rear sight RMR plate) or did you mean a clamped-on rail on the barrel? A barrel-clamped pic-rail with a red dot mounted to it would definitely have the Rube Golberg vibe!
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This would take my mall-ninja creation to a whole new level.:ninja:

I mean clamped directly on the barrel. The cleanest mount would be to machine a mount with an RMR footprint on the top and a split-ring of the barrel diameter on the bottom. Similar to the method of mounting front aperture iron sights on a target rifle... like this RPA ladder front sight, only putting an RMR on it instead of the front aperture sight globe.

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Putting it on the slide would negate the intended benefit, which is to take all of the potential deviation of slide lockup to barrel out of the equation. I wouldn't try this with the adapters you are thinking of, you really need as much surface area as possible clamping onto the barrel. I'm pretty sure the RMR would be able to handle vertical motion of the barrel as locks and unlocks the breach, since most seem to handle being accelerated pretty violently when they are ridding on top of the slide.
 
Hmmmm.........interesting. It's like you're lighting the pipe in front of Julian.

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