Base line ...Measure spring O.D. and write it down ...... Measure wire diameter and write it down ..... SUBTRACT wire diameter X2 from the spring O.D. and there is the @ spring I.D. ( actual guide size with be +/- pending application )Generally when installing the guide it should be light to snug fit requiring some push to get it inside spring. Only trial and error ( AKA: Experience ) will get you the knowledge of whats just right.* DEBURR the ends of coil so not to gall the guide when pushed on & smooth up the flat surfaces.Have fun and good luck ...
Educate me if you would please, because while honestly not sure which of a half dozen forums I read it on, it was recommended to set the spring before measuring and making guides. Is it something that should be or does it not matter if it's set or unset??
Quote from: Motorhead on October 07, 2021, 11:57:56 AMBase line ...Measure spring O.D. and write it down ...... Measure wire diameter and write it down ..... SUBTRACT wire diameter X2 from the spring O.D. and there is the @ spring I.D. ( actual guide size with be +/- pending application )Generally when installing the guide it should be light to snug fit requiring some push to get it inside spring. Only trial and error ( AKA: Experience ) will get you the knowledge of whats just right.* DEBURR the ends of coil so not to gall the guide when pushed on & smooth up the flat surfaces.Have fun and good luck ...Educate me if you would please, because while honestly not sure which of a half dozen forums I read it on, it was recommended to set the spring before measuring and making guides. Is it something that should be or does it not matter if it's set or unset??
Thanks fellows for all the info so far. I'm learning more and more everyday on this particular subject. Does anyone know "from experience" just how much power "ie" FPS you loose by going to a larger diameter guide? Is there such a thing as too large? I know you have to at least get the spring around it and back in the gun but other than that there is a lot of trial and error I would think. And from the target vs. hunting application am I to assume that a tighter fitting guide will reduce power but aid in accuracy by having a smoother shooting gun?ThanksRay
Someone posted a video here yesterday in a different thread of a guy setting the spring before making the guides. He has a nice press to set them, and the ID increased after the set. If I can find the video I'll post it here.
Paul Watts shows how much the ID of a spring opens up after the spring has taken a set. In other words, if you make a fitted spring guide, it needs to be for the spring ID after the spring has been set (by full compressing it to coil bind). If you make a tight spring guide based on a new unused spring's ID, the guide may be too loose after the spring has taken a set. A loose spring guide allows the spring to twang. Sticky grease should help for that, but setting the spring before sizing the guide would be the better approach:
Seems like a satisfying outcome, Ray I am surprised that so little interference still works when the spring is at rest under normal installed preload. It is as if the guide is wrapped in one layer of office paper. A useful data point.