P94 comped slide mod

[jonsP944]

Taking inspiration from the p365xl comp, I was thinking it would be possible to slide comp a P94 and/or a P944.

The P94 might make the best candidate with the possibility of no barrel modification. The key would be if a P93 barrel has the same swinging link system as the P94.

If this is the case I would imagine you could drill out the barrel hole in the slide slightly and insert a pipe with same id as the id of the original slide hole. Using a pipe that has an od larger than the new slide hole size and lathe the outside of the end of the pipe going into the slide hole to fit snugly in the slide barrel hole then pin the thicker part of the pipe to the side of the slide. The pipe should be the same length as the difference in the two barrels plus the length of pipe inserted in the slide barrel hole. I suspect it won't be necessary, but the hole of the longer tube in the slide could be enlarged to allow the barrel to angle up as the slide moves over it. It works on the Sig with an additional .25" of difference in barrel length, so it seems feasible. The barrel end of the slide should be slotted leaving enough material to not interfere with the sight block or maybe the front sight block could be slotted to move the sight back to allow more material to be removed for the comp (this is how the P365 xl comp is)

The P93 has a 3.9" barrel vs the 4.25" of the P94. That's .35". That's probably only enough room for a .25" comp slot.

I'm not sure what length of comp would be ideal. The 365xl has .6" to work with. I'm not sure if this was engineered to be optimal or if they just did the same thing and took the next shortest barrel in the lineup to make a slide comp.

I suspect .35" will be effective, but .6" would work better. It wouldn't be outside the realm of possibility to just have .6" cut off of a P94 barrel. This would eliminate the need to verify swinging link compatibility between the two barrels and open up the possibility to comping the P944 with a cut and crowned P944 barrel. The shorter barrel might necessitate a lighter spring, but hotter loads might also solve any cycling problems and should actually make the comp more effective. A 3.65" barrel is only .05" shorter than a standard P365 xl barrel and accuracy doesn't seem to be a problem for the P365 at 3.1", so I would imagine a 9mm or 40 would be fine at 3.65"

I would like to get an exta slide and barrel (they seem to be available) to try this with so that I would have the ability to put the gun back together in stock format with original parts.

Does anyone see anything functionally wrong with these ideas?

 

[jonsP944]

I still want to try this, but I have a couple more potential ideas for accomplishing essentially the same thing that might simplify the slide modification. If the P93 slide will function on a P94 you could drill the slide hole and insert a slide extension and put the comp ports in just the extension. If you could find a way to match the profile of the front of the slide it might not look too bad and fill in the front of the frame.

My other idea would be to do this with a P95 slide on a camblock P944. I seem to recall reading that the P95 slides won't work, but in comparing diagrams it appears that the slide rails and where the camblocks contact are identical. The P944 has a trigger pin whereas the P95 does not. I don't think this will be an issue as the trigger bars have the same part number as do the hammers and many other parts. The camblocks and barrels (other than the obvious length difference) are slightly different, but only where they interface with each other. The parts of both camblocks that contact the frame appear to be the same. The P95 parts kits are a bit cheaper than other P series parts kits (at least based on my last gunbroker check). This might be worth a check.

Any input would be appreciated.

 

[jonsP944]

I still want to try this, but I have a couple more potential ideas for accomplishing essentially the same thing that might simplify the slide modification. If the P93 slide will function on a P94 you could drill the slide hole and insert a slide extension and put the comp ports in just the extension. If you could find a way to match the profile of the front of the slide it might not look too bad and fill in the front of the frame.

My other idea would be to do this with a P95 slide on a camblock P944. I seem to recall reading that the P95 slides won't work, but in comparing diagrams it appears that the slide rails and where the camblocks contact are identical. The P944 has a trigger pin whereas the P95 does not. I don't think this will be an issue as the trigger bars have the same part number as do the hammers and many other parts. The camblocks and barrels (other than the obvious length difference) are slightly different, but only where they interface with each other. The parts of both camblocks that contact the frame appear to be the same. The P95 parts kits are a bit cheaper than other P series parts kits (at least based on my last gunbroker check). This might be worth a check.

Any input would be appreciated.

In doing further research I have found that the P95 slides will not work on the P944 camblock frame. The P95 has a set of lower slide rails that thr P944 does not have. Also, due to the slide catch placement the P93 slide will not work on a P94 frame.

 

[NikA]

The way this is normally accomplished as an aftermarket add-on is to thread an extended barrel and use a threaded comp. Does the 94 barrel function in the 93 slide? If so, seems like there could be enough extended length to thread and you would have your choice of threaded comp.

Messing with the geometry of the slide hole is not generally a good idea, it is precisely clearanced for the tilt that happens during lock/unlock and might fail to function or provide diminished accuracy if modified.

 

[jonsP944]

The way this is normally accomplished as an aftermarket add-on is to thread an extended barrel and use a threaded comp. Does the 94 barrel function in the 93 slide? If so, seems like there could be enough extended length to thread and you would have your choice of threaded comp.

Messing with the geometry of the slide hole is not generally a good idea, it is precisely clearanced for the tilt that happens during lock/unlock and might fail to function or provide diminished accuracy if modified.

From what I've read threaded comps and slide comps are close to equally effective. Ported barrels are reportedly the most effective. I'm in California, which means no threaded barrels for me. I would consider having a barrel ported, but I like the idea of using a shorter barrel working as originally intended.

I have been considering barrel tilt. I haven't thoroughly researched it, but it seems like the axis of rotation is at the back of the barrel meaning most of the deflection will occur at the front of the barrel. With this being the case and the slide stopping at the same point with relation the back of the barrel, it would seem the angle wouldn't really be different than oem at the back with a shorter barrel and that the bevel/angle at the back of the modified barrel hole in the slide should match oem. The front of the barrel will be going through a longer hole than oem, so it would seem some extra material would need to be removed from the top of the hole toward the front of the slide with a slight oval at the end. With material already being removed from that area for the comp it seems feasible. The goal would be to have the tip of the barrel sitting the same distance in the slide hole as oem and that the hole in the slide from the tip of the barrel to the back (when the slide is home) be dimensionally the same as oem. This should stabilize the end of the barrel the same as oem.

I would like to try using a P93 barrel on a P94 at first as as it would require no barrel modification. This is significantly less than what sig is doing with their .6 inch length difference going from P365 XL to XL comp. If it works it might be worth having a barrel cut and crowned to see if .6 is attainable.

I need to obtain a swinging link P94 before I can start down that road, though. I have my eyes on one (this is another situation complicated by living in California). If I get one and am able to put the rest of the project together I will post back.

 

[roylt]

I have tinkered on the P-guns some but not really a smith.
Glock used to offer a ported slide and barrel pistol. https://eu.glock.com/en/Technology/Compensator-pistols

The end of the slide "holds" the barrel in my opinion so your idea to sleeve the slide to make the holding point farther back from the end seems like a hard thing to accomplish.

I have put a P94 barrel in a P93 slide / frame to yield an extended barrel but never thought to shorten the barrel.

Also you being in CA I'm not sure how the laws apply to modified pistols. IF you do get all this done would it be legal to own? I'd do a lot of research on that before I mess with breaking a law. Just my 2 cents.

 

[NikA]

Just watched a video on the Sig system you are suggesting duplicating. In that system, the precision fit between the barrel and the slide is located in the middle of the slide before the comp. Based on that design, I would bet it is easier to add material to the front of the slide for the comp. I would braze or TIG a rough sized block to the front of the slide, bore it to exactly the dimensions of the original slide hole, overbore the block in front of the slide to account for the barrel tilt (maybe at a taper), then cut the comp slots and blend to the original slide.

All of this will be much more work than porting the barrel and slide. If I wanted the same result for minimum cost/effort, I'd port if for legal reasons I couldn't go the easy route and add a barrel comp.

Have you looked at barrel comps that clamp versus thread on? I image such things exist, they certainly do for rifle applications.

 

[jonsP944]

I have tinkered on the P-guns some but not really a smith.
Glock used to offer a ported slide and barrel pistol. https://eu.glock.com/en/Technology/Compensator-pistols

The end of the slide "holds" the barrel in my opinion so your idea to sleeve the slide to make the holding point farther back from the end seems like a hard thing to accomplish.

I have put a P94 barrel in a P93 slide / frame to yield an extended barrel but never thought to shorten the barrel.

Also you being in CA I'm not sure how the laws apply to modified pistols. IF you do get all this done would it be legal to own? I'd do a lot of research on that before I mess with breaking a law. Just my 2 cents.

I have looked into the legality a little bit. Modification would become illegal if it makes the gun less safe or harder to identify. By using a slide that came with the gun the outward appearance would only be changed by some holes in and a pinned insert in the slide. It would have the same shape, dimensions and markings as the non modified gun. Of course consulting a lawyer specializing in California gun law on this would be wise prior to putting a modified slide on a gun. As far as safe, that would be the goal. I should definitely consult a gunsmith on that part and feasibility in general before accumulating parts for this.