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Bullmoose · June 11, 1999, 01:36 AM

I am thinking about building a 45S and like the backyard mechanic that I am I would like to make the mods with my own parts list not a conversion kit from a pro shop. Of course my list costs less than half of the pro kit, but I think that in some ways it will be better.
My question is mainly concerning use of a Springco Guide Rod System and the oversize firing pin stop. I can't seem to find out how much extra resistance the guide rod system provides and I do not fully understand the function of the firing pin stop retarding the timing of the slide coming back. Does the square surface on the firing pin stop provide additional resistance as the hammer is cocked by the slide therefore retarding the slide and holding the shell in the chamber a little longer allowing the pressure to drop some before it opens? Do you just fit the stop as normal, but leave just break the square edge? I am trying to identify if my modifications will provide the correct slide velocity to allow function without promoting battering. Ace Guns provides a 30# spring, I'll be using a 26# max, but the unknown resistance from the Springco might make everything work out just fine. I will be installing a heavy duty firing pin spring, shortened firing pin, heavy duty extractor and lowering and flaring the ejection port to reduce battering the brass. I am thinking that it might be prudent to install a ramped bbl to provide the maximum support, but Ace doesn't and I don't think that the new Springfield 45S does either. That raises another point: if I port the slide and bbl ala the Springfield, how does it affect the slide velocity? Would a lighter spring be called for? I guess the only way to identify the optimum recoil spring weight is to start with a fairly heavy one and increase or decrease the weight as necessary to find the highest weight spring that will still allow the slide to work at a rate to feed the brass? Hope that the 10 or 12 questions isn't expecting too much (BG). Thanks, Jim
PS: There isn't a big rush on this as I am working on a Series 70 in 45ACP with 2 top ends, one the 70 with minor mods, one a military chopped and compensated. I am doing more procrastination than work right now, but it is faily well ready to go together. I will be doing the checkering, mag well flaring, trigger work, probably sight work on the 45S before I really decide about the details that really count. Another way to procrastinate I guess.

June 11, 1999, 01:36 AM	#1
Bullmoose Senior Member Join Date: February 10, 1999 Location: Placentia,CA,USA Posts: 143	I am thinking about building a 45S and like the backyard mechanic that I am I would like to make the mods with my own parts list not a conversion kit from a pro shop. Of course my list costs less than half of the pro kit, but I think that in some ways it will be better. My question is mainly concerning use of a Springco Guide Rod System and the oversize firing pin stop. I can't seem to find out how much extra resistance the guide rod system provides and I do not fully understand the function of the firing pin stop retarding the timing of the slide coming back. Does the square surface on the firing pin stop provide additional resistance as the hammer is cocked by the slide therefore retarding the slide and holding the shell in the chamber a little longer allowing the pressure to drop some before it opens? Do you just fit the stop as normal, but leave just break the square edge? I am trying to identify if my modifications will provide the correct slide velocity to allow function without promoting battering. Ace Guns provides a 30# spring, I'll be using a 26# max, but the unknown resistance from the Springco might make everything work out just fine. I will be installing a heavy duty firing pin spring, shortened firing pin, heavy duty extractor and lowering and flaring the ejection port to reduce battering the brass. I am thinking that it might be prudent to install a ramped bbl to provide the maximum support, but Ace doesn't and I don't think that the new Springfield 45S does either. That raises another point: if I port the slide and bbl ala the Springfield, how does it affect the slide velocity? Would a lighter spring be called for? I guess the only way to identify the optimum recoil spring weight is to start with a fairly heavy one and increase or decrease the weight as necessary to find the highest weight spring that will still allow the slide to work at a rate to feed the brass? Hope that the 10 or 12 questions isn't expecting too much (BG). Thanks, Jim PS: There isn't a big rush on this as I am working on a Series 70 in 45ACP with 2 top ends, one the 70 with minor mods, one a military chopped and compensated. I am doing more procrastination than work right now, but it is faily well ready to go together. I will be doing the checkering, mag well flaring, trigger work, probably sight work on the 45S before I really decide about the details that really count. Another way to procrastinate I guess.