Tuning How can a pin probe seat deeper than stock FX pellet probe?

[Golani]

First of all, thanks for all replies

I have checked the magazine over and over. It seems to lock correctly. I have absolutely no problems when I use the pellet probe. The problem of the diving slugs only occur with the pin probe.

There is something I find odd with the .30cal magazine. Two buddies of mine also have an Impact M3. And we all have slightly different magazines. Two of us have a mag that takes 23 rounds. One of us has a mag that is for 20 rounds only. Both our 23 round magazines are also different. I was planning to test some slugs to find out what my FX likes. So I got several different slugs. The heaviest and tallest I have is a Javelin 68grn. I can fit it without any problems in the magazine and it also rotates normally. While my buddy can only fit up to a 54grn H&N.

For the moment I opted to get a Huma high flow dual hole V2. It should arrive here tonight. We’re lucky to have Krale, an air gun specialist here in the Netherlands. They offer same day delivery. I can put it on the gun tonight and test it at the range tomorrow.

I can try to debur the standard FX transfer port later. And keep an eye out for a possible problem with the fitment of the magazine.

Cheers,
Nick

 

[stovepipe]

First of all, thanks for all replies

I have checked the magazine over and over. It seems to lock correctly. I have absolutely no problems when I use the pellet probe. The problem of the diving slugs only occur with the pin probe.

There is something I find odd with the .30cal magazine. Two buddies of mine also have an Impact M3. And we all have slightly different magazines. Two of us have a mag that takes 23 rounds. One of us has a mag that is for 20 rounds only. Both our 23 round magazines are also different. I was planning to test some slugs to find out what my FX likes. So I got several different slugs. The heaviest and tallest I have is a Javelin 68grn. I can fit it without any problems in the magazine and it also rotates normally. While my buddy can only fit up to a 54grn H&N.

For the moment I opted to get a Huma high flow dual hole V2. It should arrive here tonight. We’re lucky to have Krale, an air gun specialist here in the Netherlands. They offer same day delivery. I can put it on the gun tonight and test it at the range tomorrow.

View attachment 507237

I can try to debur the standard FX transfer port later. And keep an eye out for a possible problem with the fitment of the magazine.

Cheers,
Nick

Don't use the pin probe with the dual port "bridged" transfer port until you have first solved the feeding problem with the pin probe and the standard transfer port. The reason why is because a misaligned projectile being forced over the thin bridge section of the dual port opening will break the bridge.

stovepipe

 

[stovepipe]

A 3rd party magazine made specifically for the Impact M3 might solve the alignment problem. STUD magazines might be worth checking out. Do a Youtube search for "FX Impact M3 magazine".

Edit -- added the following:
Here is the first youtube vid I found. Watch the whole thing and pay attention to when he shows the alignment of the projectile with the hole. Also he mentions how the slot that fits around the barrel end is perfect, whereas the FX mags simply are not. He is actually using the 30 cal version, just like your impact.

Golani, this STUD magazine looks like a winner. There may be other 3rd party mags that are just as good -- I only did a quick search and this is what I found first.

stovepipe

 

[DesertSilver]

Try a Orion magazine. While the one I have isn't a.30 but a.22 the tolerances are much tighter for slugs than the FX original magazine. Looking at the marks on the slugs they look like they're catching on the magazine not the barrel/dual port.

 

[Airgun-hobbyist]

So, hand feeding a slug into the breech and than further push it with the pin probe is no problem.

I do notice ‘bite marks’ on the slug when I push them back out. Showing that the do hit something on the way into the barrel. (Only when fed from the magazine with the pin probe. When I use the pellet probe there is no problem)

View attachment 506794

This is the tip of the slug dipping into the transfer port. The pin probe acts as a pivot point for flat based slugs and pellets, allowi g the frint to nose down into the port. The original FX tube style of probe pushes evenly around the outside circumstance and pushes consistently in doing so, and doesn't allow the pellet or slug to dip as it's fed.

 

[coastal drifter]

This is the tip of the slug dipping into the transfer port. The pin probe acts as a pivot point for flat based slugs and pellets, allowi g the frint to nose down into the port. The original FX tube style of probe pushes evenly around the outside circumstance and pushes consistently in doing so, and doesn't allow the pellet or slug to dip as it's fed.

If it works don't fix it

 

[stovepipe]

First of all, thanks for all replies

I have checked the magazine over and over. It seems to lock correctly. I have absolutely no problems when I use the pellet probe. The problem of the diving slugs only occur with the pin probe.

There is something I find odd with the .30cal magazine. Two buddies of mine also have an Impact M3. And we all have slightly different magazines. Two of us have a mag that takes 23 rounds. One of us has a mag that is for 20 rounds only. Both our 23 round magazines are also different. I was planning to test some slugs to find out what my FX likes. So I got several different slugs. The heaviest and tallest I have is a Javelin 68grn. I can fit it without any problems in the magazine and it also rotates normally. While my buddy can only fit up to a 54grn H&N.

For the moment I opted to get a Huma high flow dual hole V2. It should arrive here tonight. We’re lucky to have Krale, an air gun specialist here in the Netherlands. They offer same day delivery. I can put it on the gun tonight and test it at the range tomorrow.

View attachment 507237

I can try to debur the standard FX transfer port later. And keep an eye out for a possible problem with the fitment of the magazine.

Cheers,
Nick

Hi Golani. I found another Youtube video that you might want to watch. He clearly favors the Stud magazines, but he has original FX, Orion, and Stud mags there that he has used. He talks about and shows how well each of his mags align his slugs/pellets.

stovepipe

 

[Bigragu]

I know it’s an old topic but I was wondering if you ever found out.

I just switched to a heavy liner in my .30cal Impact M3 for shooting slug. At the same time I fitted a Huma pin probe. I thought I was doing good.

But it’s been a nightmare since. I went from a small group shooting, accurate FX with pellets to a nightmare on slugs.

I was shooting Minute of Barndoor groups. Just insane. I also directly noticed that feeding a slug from the magazine into the barrel became so hard that I needed my other hand to brace the rifle. Otherwise I could not close the gun.

In one magazine I had the occasional slug that would feed without problems. Also the chrono was showing a spread of about 80fps over 23 shots. I really felt lost.

So last night while fiddling around and overthinking the problem I noticed that when you push a slug from the mag it seems to tip over real easy. Pushing it with a point just slightly off-centre does that. So I changed back to the standard FX pellet probe. I test fired 5 rounds into a trap inside my house. Just to check if feeding a round would be easier. To my relief it fed without any extra effort.

I was not yet able to test for speed and accuracy. But I am hopeful.

But it did leave me puzzled. Everywhere I look it is recommended to use a pin probe for better and more airflow. It can’t be I’m the only one having this problem! Can it?

I have since switched back to the pellet probe. In the last three years I’ve gotten into competitive benchrest and once that type of accuracy is achieved, it’s all about consistency and the pin probes could not give me that consistency. So all my fx guns today have pellet probes installed, including the one I have designated for slugs and big critter control.
When fx came out with the adjustable pin probe I was probably the first to see its showcase video. Right away I caught the mistake of its design. Yes the probe can be adjusted forward to push the projectile into the barrels lands(as described by the YouTube South African hippie), but what he didn’t catch or explsin was your mag couldn’t be inserted because the pin protruded out into the mag slot. Bad design, very misleading.
Pin probes offer, what, another 15 fps maybe, if that? If you take the time and finger your pellet probe while it protrudes halfway in the mag slot, you’ll see a lot of up/down play. Yes, it will center itself into the barrel breech upon entry but that doesn’t guarantee your ammo is being pushed in concentric to the barrel. I’ve seen . pin probes tilted up, like as if the owner just gorilla muscled a projectile into the barrel, putting a slight bend upward on the pellet probe rod. So if the point of the pin pushes at the upper top portion of a slugs dish base, it’ll force the front of the slug tip tilted down. But a pellet probe will catch the entire perimeter of the slug/pellets skirt, which is a good thing.

Looking at the different transfer ports that Hun displayed, you can see some of the differences in widths on the end with the alignment notch. The wider ones will have the edges of the transfer ports lower, requiring the pellet probe to be adjusted further forward.
In my experience, I’ve learned not to mix match one makers pellet probe to another maker of the brass TP. You’ll have transfer port alignment issues. Me personally, I only use Humas pellet probes and transfer ports. No need to port those out, they’ve allowed plenty of opening for the air to go thru.
I also cannot stand the brass TP with a pellet hole on one side and a bridged opening on the other side. Who the heck is going to switch back and forth on those? 99.9% will opt for the largest of openings. Air seeps out on that extra hole, I’ve witnessed it, especially on fx guns with a grub screw cap on top of the brass tp, that fx used to drill out the TP hole in the block. If you’ve got a dual hole tp, do yourself a favor and either buy a Huma one or JB weld plug thst unused hole, as I once did. Very easy to do

 

[Golani]

So the weekend has passed and I have tried several things.

As per suggestions the problem is with the alignment of the pin and the slug in the magazine. The thing is that the standard FX magazine fits good infront of the barrel, I think the problem is that it’s so ‘wide’. Like I said before, I can fit the smallest slug I have, a 45,5grn ZAN, but also the largest I have for testing. In my case a 68grn Javelin.
They are maybe even 2mm larger than the smallest slugs.

When the 45 grainers are in the mag they rattle and misalign. Then when the pin probe pushes it forward it naturally dips south and gets stuck on the sharp edges of the transfer port. It almost looks like it needs smoothing the ramp, just like when my old Colt .45 barrel ramp was smoothed out to guide a round from the mag into the chamber.

When the long slugs are in the mag there is significant less rattle. They also feed without any problems. The noses don’t dip because they remain centered in the magazine because of the additional length.

So I guess the problem is with the loose fitment of the smaller slugs in the magazine. Maybe an improved magazine will not have this issue. I have heard of the magazines mentioned by you guys. I also know of an all aluminium magazine from eagle vision. They close with a magnet cover. They come in two different versions. One for pellets and one especially for slugs.
They do cost a bit. Almost a € 130,-

So having checked all this out I am satisfied that the fitment of the magazine in the impact is correct. I can now choose for several options. Ditch the pin probe and use the pellet probe, use the dual hole Huma bridged transfer port or try out another magazine.

For now I did fit the Huma transfer port. I started testing with two weights of slugs. I am testing about 10 different makes and weight slugs to figure out what my gun likes best. After that I can see if the pin probe brings me more than the pellet probe. I can always switch them out later.

Thanks, Nick

 

[stovepipe]

So the weekend has passed and I have tried several things.

As per suggestions the problem is with the alignment of the pin and the slug in the magazine. The thing is that the standard FX magazine fits good infront of the barrel, I think the problem is that it’s so ‘wide’. Like I said before, I can fit the smallest slug I have, a 45,5grn ZAN, but also the largest I have for testing. In my case a 68grn Javelin.
They are maybe even 2mm larger than the smallest slugs.


View attachment 508285

When the 45 grainers are in the mag they rattle and misalign. Then when the pin probe pushes it forward it naturally dips south and gets stuck on the sharp edges of the transfer port. It almost looks like it needs smoothing the ramp, just like when my old Colt .45 barrel ramp was smoothed out to guide a round from the mag into the chamber.

When the long slugs are in the mag there is significant less rattle. They also feed without any problems. The noses don’t dip because they remain centered in the magazine because of the additional length.

So I guess the problem is with the loose fitment of the smaller slugs in the magazine. Maybe an improved magazine will not have this issue. I have heard of the magazines mentioned by you guys. I also know of an all aluminium magazine from eagle vision. They close with a magnet cover. They come in two different versions. One for pellets and one especially for slugs.
They do cost a bit. Almost a € 130,-

So having checked all this out I am satisfied that the fitment of the magazine in the impact is correct. I can now choose for several options. Ditch the pin probe and use the pellet probe, use the dual hole Huma bridged transfer port or try out another magazine.

For now I did fit the Huma transfer port. I started testing with two weights of slugs. I am testing about 10 different makes and weight slugs to figure out what my gun likes best. After that I can see if the pin probe brings me more than the pellet probe. I can always switch them out later.

Thanks, Nick

Hi Golani. Personally, I would really hesitate to do anything to the brass breech opening that is near the magazine. I wouldn't try to make it more beveled or funnel-shaped (I know what you mean about the ACP -- mine is a bad off-brand -- thus my handle -- stovepipe). I guess as a last resort I might try that, but first I would try a different magazine -- specifically I would try the Stud magazine. You might want to check the specs to see what the maximum length of slug it holds before purchasing. Here in the U.S.A., the Stud magazine is the same price as an original FX magazine ($70). I don't think the Stud magazine can possibly be worse than the FX mag. Worst case is that the Stud mag has the same problem as the FX mag and you have an extra mag. I saw the Eaglevision mag and I really don't like that it is aluminum. For most things I prefer metal rather than plastic, but in the case of a soft lead pellet/slug getting moved around in a magazine -- I feel better about plastic. The Orion mag, according to the video above, doesn't line up slugs/pellets any better than the FX mag. I know when you watch these videos, the slugs/pellets might not look as perfectly centered or off-center as what the guys are saying because of the camera angle, so you just gotta trust that what they are saying is true. I believe 'em in this case. I actually ordered two Stud mags for my 30 cal Maverick yesterday after taking a close look at how not-quite-centered my NSA 54.5 grain slugs are in my FX mags.

All of the above stuff I said is just my opinion -- nothing proved, nothing disproved, and nothing guaranteed. I know the frustration of having a pin probe jam slugs and the good feeling I had/have after getting the problem fixed. Not being able to use a pin probe when you're supposed to be able to is like buying a 4-wheel drive truck and finding out that the 4-wheel option only works on smooth paved roads -- not off road.

stovepipe

 

[Golani]

I won’t try to make the ramp more bevelled. It was just something I thought about.

The problem with the stud magazine is that they aren’t available from a shop in The Netherlands or even Europe. Silly thing is I have to pay $ 50,- for postage from the US and pay additional customs fees. So that’s $ 120.- for the mag incl shipping + 21% tax makes $ 145,- and € 45,- additional import duties and checking in fees. The euro is about the same as the USD so that’s roughly $ 200,- for a stud magazine delivered to my door. Postage prices have gone insane. Not just over the Atlantic. Here in Europe postage is also expensive.

So the only readily available option for maybe a better magazine is an eagle vision.
That’s € 127,- delivered.

For the time being I will use the pellet probe and the dual hole high flow Huma transfer port. At least during testing. I first want to find out what slug does best in my rifle.

Thanks all for taking the trouble to think about the problem and for the replies.

Cheers, Nick

 

[orion]

If the needle tip of the probe is longer than the thickness of the wheel where the pellet is hold on the magazine, the needle will push the ammo into the barrel but because is longer than the wheel holding the ammo the thicker part of the probe hasn't enter the hole where the ammo used to be and the spring will rotate the wheel on top of the needle point causing a jam. This will affect any magazine, of course if the wheel is thicker on some mags more than other then on those it will work better.

TLDR: do not extend the needle point of the probe too long, make sure when the ammo is pushed out of the magazine the thicker part if the probe is engaged in the hold where the ammo was, rotation of the wheel should only happen when moving the probe back not forward.

That's why you won't have problems with pellet probe or if you push the ammo faster into the barrel.

Hope it helps

 

[Golani]

If the needle tip of the probe is longer than the thickness of the wheel where the pellet is hold on the magazine, the needle will push the ammo into the barrel but because is longer than the wheel holding the ammo the thicker part of the probe hasn't enter the hole where the ammo used to be and the spring will rotate the wheel on top of the needle point causing a jam. This will affect any magazine, of course if the wheel is thicker on some mags more than other then on those it will work better.

This could be a problem in the time when people made their own pin probe. I remember seeing a YT video from Earnest Rowe where he was experimenting with the length of the pin.

But these days with commercially made pin probes I think it’s not an issue anymore. At least FX and Huma know what the length should be.

I’ve got a Huma pin probe that is the same overall length as the pellet probe. The pin easily clears the body width of the .30cal magazine in my rifle.

Like I said before, I think the problem is the loose fitting of the magazine. That causes the smaller slugs to get misaligned.

 

[stovepipe]

I won’t try to make the ramp more bevelled. It was just something I thought about.

The problem with the stud magazine is that they aren’t available from a shop in The Netherlands or even Europe. Silly thing is I have to pay $ 50,- for postage from the US and pay additional customs fees. So that’s $ 120.- for the mag incl shipping + 21% tax makes $ 145,- and € 45,- additional import duties and checking in fees. The euro is about the same as the USD so that’s roughly $ 200,- for a stud magazine delivered to my door. Postage prices have gone insane. Not just over the Atlantic. Here in Europe postage is also expensive.

So the only readily available option for maybe a better magazine is an eagle vision.
That’s € 127,- delivered.

For the time being I will use the pellet probe and the dual hole high flow Huma transfer port. At least during testing. I first want to find out what slug does best in my rifle.

Thanks all for taking the trouble to think about the problem and for the replies.

Cheers, Nick

Edit: I just now noticed that Golani already mentioned the two different Eaglevision mags -- one for pellets and one for slugs, so I guess this post is redundant. I could have deleted the whole post, but maybe the sale price is worth mentioning.


I noticed that the Eaglevision mag comes in a pellet version and a slug-only version. It also looks like it's on sale -- but this is a google search from the U.S.A.

You can see the difference between the pellet and slug version. The slug version has long teeth separating the slugs. Whenever I go to Krale's web site, I only see the pellet version.

stovepipe

 

[Golani]

I know. Krale only has one version on its website. But Huma air has a dedicated slug version. Huma is Dutch and situated in The Netherlands.