FN SLP Reload Practice Jam

[Firetoad]

I was practicing reloading my new FN SLP (18" Barrel SLP with Nordic +1) from the sidesaddle today. I found a problem while dropping one into the ejection port that I am not sure what the source of the issue is.

The reload entails the following:

- Going to slidelock

- Unshoulder weapon and drop butt of weapon into my right hip

- Maintain strong hand on weapon with muzzle end in my sight plane with ejection port slightly bladed/biased toward ground from vertical

- Strip round from sidesaddle and come around from underneath the shotgun

- Drop round in through ejection port

- Hit slide release

At this point, every so often I get the rim of the cartridge dropping down onto the lifter, nearly back to the bolt face. When I try to release the bolt, things lock up and the bolt barely moves before binding up. I literally have to dig the shell out with my fingers. The picture below illustrates the location of the shell when things lock up. The picture is after I dropped the slid release and the bolt is bound up.

I am using ST Action Pro Dummy Rounds for the reloading practice.

Is this normal given the particular style of reloading that I am performing (specifically, the orientation of the shotgun) or is something going on that requires some attention/repair? Or, could it just be the dummy rounds? I would try some live rounds, but can't get out to the range as I am watching my kiddos today. Thoughts/comments?

Would I be better off dropping the bolt/slide and reloading the magazine vs. dropping one in the chamber first? With the extension, my gun runs 7+1, so I need to get one round into the chamber during reload to keep from winding up with an extra shell and an extra step in reloading. Also, if I am only in need of one additional round in a stage, I would really like to just drop one in the ejection port and send the slide home.

[GorillaTactical]

Is your shell lifter factory stock?

The way you put the shell in the port should not influence the load, the weapon should always return to battery....whether you drop the shell in from the side, the top, etc etc etc....

Do you have this problem with actual shells or just your dummy rounds? It might be that your dummy rounds are heavily worn...

I've tried to recreate your problem by jamming a shell in the lifter with the bolt locked back and then slowly closing the chamber....but each time the bolt slides home...you might want to try a different shell and if that doesn't fix it, call FNH.

Edited November 13, 2010 by GorillaTactical

[TruePunisher]

You should be able to drop one in and send the bolt home without a problem so you are not doing anything abnormal in that aspect. By the picture, I have no idea what it is catching on.

Did you have this issue before you installed the side saddle? By looking at the picture, I assume the side saddle you have bolts through the receiver. If that bolt is in fact for the saddle and you have it too tight then it can cause binding and might be slowing the bolt down enough to the point that when it hits the shell it doesn't have enough force to close all the time. You could try removing the bolt and using the stock pin and see if you have the same issue.

ETA: I'd get a +2 tube and ditch the +1 as you are really limiting yourself... just a suggestion.

Edited November 13, 2010 by TruePunisher

[Firetoad]

Thanks all for the replies! After an hour or two of intense study, I did figure out the problem.

First, to answer questions and suggestions from above...

- The only modification to the lifter was to bevel/radius and polish the ends/edges of the forks to keep from tearing up my thumb skin (I will eventually have c-rums weld up the forks for me). Nothing else was changed with the lifter prior to the problem.

- As far as live v. dummy rounds, I haven't had the problem before with live rounds, but this is a fairly new gun and has only had a ~ 150 rounds through it so far. The problem is rather sporadic. So, difficult to say on my end whether it was the dummy/live rounds.

- Regarding the sidesaddle, not sure if the problem existed before or not. But, I tried to both tighten and loosen the screws with no discernible difference in the feeding of the gun. Also, it is a Mesa side saddle with the Chicago screws that limit the dimensions of the tightened screws to prevent squeezing the receiver too tightly.

- Yes, I am planning on ditching the +1 and going to a +2 extension.

Now, on to what I discovered and how things seem to have been corrected with my fix.

Studying the problem closer, I found that when I would wrap under the gun and drop in a round that would jam, it would drop into the ejection port and be resting in the gun just like any other round would. However, just prior to the jam, when I pressed the bolt release, the shell's rim/brass would drop down and things just stopped.

Looking at the lifter, I noticed that the lifter was slightly biased to the bolt catch/release side of the gun as seen below. I discovered this when I noticed the lifter would slightly catch on the bolt release when pushing it up.

So, I started studying the lifter whenever loading shells through the ejection port. Then, suddenly, I had the "Ah ha!!!" moment. During the load that I was practicing, when the bolt release was pressed, the back end of the shell slightly dropped down when the back end of the bolt catch moved out of the way. No problem there really. But, when the lifter attempted to flip the shell up when the bolt started going home, the outside, SHARP edge of the lifter would catch on the bottom of shell catch and hang up. With the lifter stopped in motion while the bolt was going home and the shell's brass in the way of the bolt release, things were locked up tight. You can see the interference that I am referring to below...

To fix things, I simply beveled, radiused and polished the interfering edge of the lifter. With the sharp edge removed, radiused and polished, the lifter now just slides off of the shell catch when they come into contact with each other.

As far as why my lifter was doing this vs. others not doing this, I am not certain on that. Maybe the lifter was slightly out of spec? Maybe a tolerance stackup? Not sure, but things seem to be working correctly now. I have a match next Saturday and plan to hit the range this week to check function.

Thanks again for all of the suggestions and help everyone!

Edited November 14, 2010 by Firetoad

[dogbert41]

Are you sure you needed to do that? Maybe your trigger assembly wasn't seated correctly? I was once having a devil of a time getting my pins back in and I noticed that my loading gate was off to the side like yourse and so I was then able to straighten out the assembly and seat it correctly. Pins popped right in and gate was correctly centered. I'm thinking the Mesa Tactical pins might not force you to have it in PERFECT.

[Firetoad]

Are you sure you needed to do that? Maybe your trigger assembly wasn't seated correctly? I was once having a devil of a time getting my pins back in and I noticed that my loading gate was off to the side like yourse and so I was then able to straighten out the assembly and seat it correctly. Pins popped right in and gate was correctly centered. I'm thinking the Mesa Tactical pins might not force you to have it in PERFECT.

That very well could have been contributing to the issue. But, I did wish to run the Mesa. So, I was sort of left with having to do something. Also, looking at the trigger assembly, I noticed that there was some minor side to side play at the end of the lifter when everything was out of the gun. Adding the lifter spring to the assembly biases the play of the lifter to the bolt release side just compounding/creating the issue. Making the modification that I did, no edges of the lifter were affected that contact the shell or have anything to do with the cycling of the gun. So, keeping my fingers crossed, there should be no unintended consequences as a result of the modification.

Here is a photo of the edge that I smoothed out to prevent the lockup that I was having...

Edited November 14, 2010 by Firetoad

[dogbert41]

Looks like you polished that smooth as glass!

[Firetoad]

Fairly close to that!

I just used a dremel with coarse to fine grit stones to remove most of the material. I hand sanded with some very fine grit sandpaper and finished up with a dremel polishing bit and some polishing compound.