I am doing a little work on a freinds 5" 1911, we are fitting a ramped barrel with cone lock up. however I will also need to fit a reverse plug, I have an old plug and guide rod that will do the job, I would like to check I am going about it the right way. My understanding is the hole where the spring plug fits is bored all the way through to .500", (the plug I have is.497" dia), the plug then slides in from the rear and contains the recoil spring. Am I right or not? is there anyhting else to do to the slide. on a side note, it is a springfield armory comercial slide and it is HARD, a HSS end mill wont even look at it, will carbide be required, or will cobalt do.
If you are using a flanged spring plug you ream it to .500", then you need to remove the same thickness as the flange from the back of the slide where the plug goes - so that with the plug installed that portion of the slide is the same length as it was originally. I've personally used a good .500" drill bit to ream the slide, but depending on the hardness of your slide you may need to use something better.
A .500 reamer will work also. Back facing the recoil spring tube is not fun. I make stepped recoil caps and use a 0.5625 reamer to cut the step from the rear of the recoil spring tube. If you make your own recoil caps, use good steel, cap walls can get pretty thin.
I am using a flanged spring plug, the front section of the slide is already .500, and when I take the flange thickness (app.170") it will eliminate the smaller section of the slide I was trying to ream, now all I have to do is get a cutter that will look at slide. HSS end mills just skate off, I got a couple of carbide cutters on Ebay the other day, I will try them.
Good subject, I have a Para-Ordnance 1911 with a ramped, supported barrel with a reversed plug, and a 1 piece guide rod drilled to hold spring when assembling or dis-assembling. With a 16lb. or lower spring, I can get the gun together but I cannot get gun together with a 20 lb. spring and a 200" shock buff or even no shock buff. This is to up the 45 to a 45 Super, yes I am using 308 cases ect, just cannot figure out why this heavier spring will not fit, this 20 lb. spring messures 32 coils and a wire diameter of 48 hundredth while it seems the other springs measure 42/43 hundredths! Bad spring? or ?
Its possible you have spring stack and it will not compress enough. I would try another vendor's 20lb spring before doing anything else. I personally only use Wolff springs, if its not a Wolff try getting one of those to see if that cures your problems. PS just realised you cannot get your spring compressed enough to pin it, simple solution here just redrill the pin hole .100 further towards the end of the guide rod. That should do the trick.