Fx impact jamming using slug.

My impact was able to load both pellet and slug just find. But after I modded my probe to take out the O, it would jam when using nsa slugs. I can load pellets just fine. It doesnt jam. But when I load slugs, it always jam. This is annoying. I can no cycle a slug into my gun now. Is there a way to fix this or I have to buy a new probe. I know fx charges $8 just for shipping. How much is new probe? Dang. Didnt even increased any power with this mod. Should have left it alone but thought i can push some more fps by doing this mod. I notice the slugs are smaller than the pellets cause they are so loose in the mag. Some people even have slug turning sideways in there mag. So I'm guessing due to the smaller size, when the half circle probe push, it pushed on the top of the slug forcing the tip to till down into the brass port. Dang it.

Here is a video of my experience with jamming. First 2 shots are jsb heavy mk2. They cycle just find. Last one is the 33.5gr nsa slug. It would get jam and cant even removed the mag cause the end catches on the mag. Really annoying. 

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https://m.youtube.com/watch?v=7zOSUMYq6sA
 
My probe is similar but i have more issues with the mag not cycling properly. Do you have a single shot tray?

No I dont have a single shot tray. I perfer the mag for fast follow up shot. Now I cant use slug with the mag. It will always jam. I can still load the slug by hand by using the finger to push it into the brass end flush, then close the lever. But that is way too slow for my need. I'd like the fast follow up if I miss, i can load another round quickly. Before the mod I was able to use slug in my original fx mag. So I'm thinking its cause I cut away the O so it doesnt push evenly on all size. That is why the tip of the slug till downward and jam. With pellet it's no problem cause it's a tight fit but slug are really under size and loose. Even if a slug in pass flush with the brass end, if till the barrel up, the slug will easily slide back out. With pellet, it will stay inside.
 
Here's an easy fix:. Drill and shape the port hole on the opposite side of that probe like this one. Then drill and tap the small probe block on the opposite side so the set screw can be put in from over there. I'd go with a 4mm set screw instead of the 3mm unit that came from the factory. Drill, tap, and set screw should be less than $10.00.

BTW, I did the same mod as you and it wouldn't cycle slugs either. Every one of them jammed because it's pushing on the top of the slug and allowing it to go nose first into the transfer port. With the probe flipped like in the image below it will be pushing on the bottom and should be good to go.

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I have a hand drill and some drill bits, but no tap. I took the barrel out and insert a slug in. It's really loose and can wiggle inside the brass tube. It only stable when it gets to the liner. I slowly push the slug from the top on the slug end and its loose enough that the tip dips in and the tip of the slug catches on the end on the brass hole. My brass hole is at 90 degree. So I'm thinking of making the end where the tip of the slug catches, maybe at an angle so the slug will slide in and dont make contact with the brass hole. I'll report back after I finish filling it at an angle.

Slug tip makes contact where the Allen screw is pointing to. I will fill it at a 45 degree and see if it fix the jamming issues.

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I just barely rolled the edges on my port hole so they didn't grab and dig into the soft lead. Be careful ramping that area. It is just about where the end of the pellet skirt sits in the brass port. If you go too far there will be a hollow spot under the skirt that it is going to push air up around the pellet body and head which could cause flight issues.
 
I just barely rolled the edges on my port hole so they didn't grab and dig into the soft lead. Be careful ramping that area. It is just about where the end of the pellet skirt sits in the brass port. If you go too far there will be a hollow spot under the skirt that it is going to push air up around the pellet body and head which could cause flight issues.

Yea I can see. Kinda dig a little into the liner when I filled it. I thought that would fix it. But when I loaded another slug it still jams. Took barrel off to see where its jamming at. Now tip of slug is jamming right at the beginning of the liner is. Cant get any worst. If it ain't broken don't messed with it I suppose. I guess that's what happen when you try to mess around with a good gun. Now probably gonna order a new brass transfer port. Smh. Tip for others trying to mod their gun. Just leave it as is if its working fine. Dont try to mess with it and save yourself a lot of headaches. 

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Ok just run into more problem. Like airgun hobby motion that the probe also dig into the mag. Taking out the under side O, there is nothing left to hold the mag from rotating when the round leaves the mag. So the mag rotates and the plastics star shape digs into the probe and jams. Damn one problem after another. Should have leave my gun as it was. But seeing people modding theirs to get more power couldnt resist. My advice is do not cut away the O cause there is nothing left to hold the mag from rotating before the probe goes though and it will get caught. Might be ok for single load. But very bad mod for using mag. You even warn. Dont do it. 

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Never make the brass port wider, remove the top of the probe instead of the bottom and be sure not to cut past the midpoint on the probe. Don't make the port too long or you end up with a 90 degree wall at the end of the liner. You want a radius there to let the air transition as smoothly as possible.

The brass port on Impacts is about 90% the width of caliber which leaves 5% bearing surface on each side of the slug to hold it inline as it spans the port. This is why making the port even a tiny bit wider causes feeding problems.