I reloaded some 40 S&W 180gr LFP bullets and shortened the OAL 1.100. 15 with 4.1 gr HP38 (950fps) and 15 with 3.7gr HP38 (850 fpd). No hangups with the lighter load and 2 with the heavier load. Does this indicate week springs either the recoil spring or magazine spring? Using 4.1gr of HP38 with OAL of 1.125 hangs up about every other round. Factory Blazer 115 frangible fed great.
Its hard to say as of now. It really depends on were it hangs up. Does the slide completly miss the back of the next round and comes across the top leaving a dent in the brass or is the nose of the bullet getting stuck in the top of the breach. Very seldom (at least for me) have I ever seen a mag spring at fault for feed failure. Its usually the mag itself. I'm assuming factory mag?
If factory ammo and a lighter load from you feeds fine them I'm leaning toward neither spring is at fault. What model smith is this? Many semi-autos are very sensitive to OAL. Have you loaded any with a matching OAL to factory ammo?
Excuse the edit: Flat Points? Flat point are iffy at best for some semi auto's. My model 59 9mm won't feed a FP bullet no matter what I did, so I just quit using them. So you'll probably ask the question of why the lighter loads work. Recoil in a blow back action can do some really weird things. Hi recoil can cause much of the energy to be lost in your hand and through your arm. This will and can lead to a failure to feed. Just ask any responsible gun shop owner about selling a compact .45 to a dainty female. They won't b/c it won't feed correctly after that first shot. Not that I'm calling you a dainty female but a combination of higher recoil, fp lead bullets, and short OAL may be your problem.
Last edited by Helix_FR; 05-04-2009 at 01:54 PM..
Reason: Flat points
you can bend the ears on the mag up slightly so the rounds are a little more nose up than before. Just be careful not to go to far otherwise they will jamb to the top of the breach. The only problem with doing this is it may cause rounds that once feed properly start having problems. Just go slow and don't bend to much at a time. Load some dummy rounds and test.