[jlh820]

I put a solid stainless steel guide rod I purchased from PRP in my XDm 45. I'd also recently put a trigger kit in it and just test fired it. In getting used to the new trigger feel, I had an unplanned detonation at one point. With the new guide rod, however, what I wound up with was a double-tap bullseye, which I've got to believe the guide rod was a factor. There's almost no flip at all now, though there was little before. So, it accomplished it's goal.

That was the good news. The bad news is for the first time ever, I had 2 or 3 FTF (fail to feed). I think the likely suspect is the new guide rod. I can't see how a trigger kit would have any effect on feeding, but the weight of the new rod might impact recoil (actually it'd better)!

I think what I might need to do is go down a pound or so in the weight of my guide rod spring. As I understand it, the spring counteracts the recoil. The recoil process extracts and ejects, but it's like a limp-wristed slide racking that failed to load a round, so I've got to think that if I lowered the recoil spring, the force of the recoil would be harder and get rid of my FTF problem.

Anyone out there have experience with this and have anything to comment? Does it sound like I'm on the right track? And going to a lighter spring would be the right direction, correct?

Thanks.

 

[AZXD]

Your thought makes sense to me, if the slide isn't going back far enough to strip the next round off the magazine, a lighter spring would allow greater movement ... IMO, the trick is not to let the slide hit the stop, if you go to light on the spring, the result would be an abuse of the guns mechanical movement.

Is it possible the guide rod is creating a mechanical bind situation ?

Subscribing to see what one of the Smith's has to say about this.

 

[ranburr]

Neither mod has anything to do with your problem.

 

[jlh820]

Neither mod has anything to do with your problem.

Really? I don't doubt you, but I just never had a FTF before and had 3 in 100 rounds after the trigger kit and new guide rod. My mags are clean, never dropped and in perfect shape and the gun only has about 1000 rounds through it. I'm using FMJ PMC ammo, which I've used before without incident. There's no bind in the slide action, but 3 times it stopped with the slide open with a 1/2 loaded mag in it.

Do you think you know what the problem is, or it's just that those two mods are unlikely suspects? I just figured the added mass of the solid guide rod might have upset the balance with the recoil spring.

 

[ThumperIII]

Less recoil flip would actually allow for the slide to open more forcefully as the slide would be continuing to travel more just straight back instead of changing the direction of force by rotating around your grip pivot center. Additionally, with the added mass of the heavier guide rod the pistol would have greater inertia to resist recoil, so more energy would be directed into moving the slide. The guide added some forward muzzle weight that helps control recoil flip but the difference in weight from the stock guide is probably less than the difference between a full and almost empty magazine. The stock spring weight is selected to function correctly with nearly any normal range of commercial ammunition (from light to heavy bullet and high to low powder charge). The slide of the pistol should always open fully to impact the mechanical stop, anything less would be shortcycling the slide. The spring only acts to slow and reduce the impact force to the design level. Otherwise you could only shoot one specific load and anything lighter or heavier would fail to function. Only if using low power (competition loaded) ammo that cannot fully open the slide to contact the mechanical stop would you need to go to a lighter spring. Light spring = slide opens faster and harder, closes slower and less forcefully - heavy spring = slide opens slower, closes faster and more forcefully. For proper function both should allow full travel of the slide with your selected ammo. Unless the spring is binding on the new guide rod there should be not lessening of feeding reliability.
Slide action is a timed cycle that has to allow for the top round to be raised to position for pickup by the breech during the open portion of slide travel.
Depending on which PRP kit you installed, the springs could change the trigger pull weight, the sear rotation force and/or the striker setting weight and primer impact force. Properly installed, none of these would change ammo feeding short of a failure to ignite the primer.
Barring an incorrect part, it is more likely an installation or fitting error rather than the parts themselves. Make sure everything is installed and fitted properly so there is no binding. Your inadvertent discharge may be an indicator something is not adjusted or fitted correctly. Causing drag on the slide. Also check the magazine. Happens with only one or all? Dirty or dented mags can cause slow follower action so the top round does not get positioned.
Go back to stock. Test pistol. If no problems, install one mod part. Test pistol Etc. changing only one item at a time and verify fitting of each.

EDIT: Especially as you wrote in your other post that all the parts came from PRP, I would doubt the parts themselves are at fault in the FTFs. Most likely if the FTF is at all associated with these mods, it would be an installation or improper fitting problem.

 

[jlh820]

Your thought makes sense to me, if the slide isn't going back far enough to strip the next round off the magazine, a lighter spring would allow greater movement ... IMO, the trick is not to let the slide hit the stop, if you go to light on the spring, the result would be an abuse of the guns mechanical movement.

Is it possible the guide rod is creating a mechanical bind situation ?

Subscribing to see what one of the Smith's has to say about this.

There's no binding. Every thing's working very smoothly. I guess I'll try it some more and see what it does before changing anything else. I know too weak a spring can make the slide jam back and damage the gun, so I don't want that to happen.

I'll keep poking around and see what I can figure out. If it keeps happening, I may go with a 1# lighter spring - I think Wolf makes them - and see how that works. I've always used 230g FMJ hardball rounds with the same powder loads. I do have some mags with +3 extensions on them, but they've worked fine in the past and I believe one of the FTF was with an unmodified mag, too. The extensions are AGP Arms, Inc and have stronger springs to compensate for the additional rounds.

I keep all my original parts, too and I can always go back to the stock guide rod and see if that makes a difference.

 

[ranburr]

Neither mod you have can cause the issue you are describing. A guide rod simply keeps the spring in a straight line. I run tungsten rods in several pistols without issue. On the opposite end, you can run the same springs on a plastic rod without issue. You didn't actually change your recoil spring, which could cause what you are describing. Your trigger job has nothing to do with it. If you were getting lt. primer strikes, then I would be suspicious of the trigger work. That is not the case. I really can't comment more without seeing the gun.

 

[AZXD]

I've always used 230g FMJ hardball rounds with the same powder loads.

Try a light load (185 ?), before you change springs, or do anything else, and see what it does.

 

[ThumperIII]

In future please try to keep the dual posts (same incident subject but slightly different info and title) to a single thread. Your concurrent post Broken Grip Safety Spring is almost identical except for minor details. It is easier to respond to a single thread than remembering what was or wasn't in each. Not busting your chops yet (you are new) but I try to address issues and questions raised in the replies as well as the OP. Gets confusing who said what where. Thanks.

 

[jlh820]

In future please try to keep the dual posts (same incident subject but slightly different info and title) to a single thread. Your concurrent post Broken Grip Safety Spring is almost identical except for minor details. It is easier to respond to a single thread than remembering what was or wasn't in each. Not busting your chops yet (you are new) but I try to address issues and questions raised in the replies as well as the OP. Gets confusing who said what where. Thanks.

Will do. Sorry, about that, chief!