1911 rearward slide travel

Hello, All
Fitting a hat or flange type reverse recoil plug to a new slide, how much to shorten the spring housing? I don’t want to just cut it the thickness of the hat, what I’m looking for is a way to gauge the correct position of the slide when it contacts the recoil shoulder.


Well, I am not sure why you don’t want to cut it by the thickness of the plug hat, but, you want to take into account the thickness of the guide rod head and the slide should be able to travel enough to the rear to push the slide stop down out of locked position.

Then take into account that there isn’t always a whole lot of room. For example, some people can’t release their slides using a slingshot method because they installed a recoil buffer and others can. That is in government models. Commanders are more tricky and officer sizes even more so.

Another thing to look out for if building a commander, for example is barrel bushing conflict with the meat on the barrel ahead of the forward locking lug. Some commander barrels have meat there that shouldn’t be there. That could impede rearward travel of the slide and lead to a bad failure.

In any case, usually when using a hat style recoil spring plug you would want the hat of the plug to replace the removed material on the slide. But, like I mentioned before, the slide should come back to the rear enough for the slide stop to get fully disengaged from the slide stop notch.

P.S. also, some recoil springs are too long, as in, when fully compressed they are longer than the depth of the slide’s dust cover or in your case the depth of the reverse spring plug. If the spring is too long it will absorb all of the force of recoil impact and will get deformed.

The above is just what to look out for when you start testing. But during initial phases just make sure that you can fully release the slide stop by pulling the slide back our of slide lock position.


I assume that I DO want to cut by approximately the thickness, but my thoughts if I knew more precisely where I wanted the slide to stop, I would then know more precisely how much to cut, especially not knowing if/ how much the new 6" slide is oversized/ over length in that area.

I’ll use this as a starting point. Thanks again for all the detailed information.
Some photos of progress so far.

6" RIA Longslide 10mm, full length tactical dust cover frame, Fusion C/P/L 7" bull barrel.

Tramming X and Z




Slot Cutting


:drooling_face: milling machine


Second that


Milling machine = ability to screw parts up way faster and in many more ways with much more precision then my matrix tooling would ever allow!


If I could afford the machine I could afford to screw up a few parts.


oooeeewh buuuttons



Wasn’t that bad really, Got the PM25MV w/ the DRO’s and power feed, added the Priest Productivity package and power lift. Skipped my Mexico vacation this year, about a wash…


It would still be hard to justify getting one. My wife gave me fits about my lathe and it was free. She still jabs me every now and then “you don’t ever use it”. I reply yeah but when I do I’m glad I have it.


Yea, have an 1975 1024 Jet lathe
Use it a few times a year, but it will do about anything.


All this for the price of a vacation?

This creates a perpetual vacation spot in your home,

how much do I need to cough up for this vacation I suddenly feel like a travel agent?


I’m a little under 4K all in, however I already had a good supply of end mills, ball mills, radius mills, and various other cutters, tooling, collets, clamps, rotary table, vice, etc I have been collecting for some time. Had a Harbor Fright mini a while back, and a horizontal mill from the 1930’s that was about worth its weight in scrap. replace the tools, keep the tooling!


Yeah I had to part with one my last move and would prefer to upgrade, 4k is at least a goal, thanks :+1:


I actually did a lot with that little mill, added a belt drive, X Power feed, some DROs, new controller, new motor…
Here is the write up I did over 10 years ago.

Adding an inexpensive DRO to the mini mill

Started with the X-axis, went through a couple of designs, this worked out best with out reducing the 9.065 total travel. Ended up with tapping 1 hole in the Y-axis carrier. Indicator travels, slide stationary.




This is the only hole I tapped in the mill.

Next was the Z-axis, 7.675 travel, probably the easiest one:


Yea, I know, only one attaching bolt, but a very tight fit in the keyway keeps it solid. If it starts moving around at a later date, I can always tap a second bolt in. Indicator fixed, slide travels


Last was the Y-axis, 3.750 travel, tricky to get required clearances, indicator travels, slide fixed.




Belt conversion:


Limitations of the mini mill:

Not a lot of travel.

Hard to get X-axis gibs adjusted tight enough to obtain desired results and still be able to run power drive at slower settings. Y-axis gibs not very long, again contributing to adjustment difficulties.

Z-axis large amount of backlash, mostly due to rack and pinion instead of leadscrew design.

Other then the obvious limitations of an inexpensive mini, I think it will work out.
I have about $250 for the mill, $175 for the power drive, $175 for the belt conversion, $100 for the 3 DRO’s, and about 40 hrs shop time into it.

Update: leaving the X-Axis leadscrew nut loose enough to allow about a half a turn of backlash actually helps the situation, allowing for tighter gibs. Go figure. Maybe the Nut/ Leadscrew alignment needs looking into.