Hatsan AT44 Long .25 magazine indexing problem

[GoneShootn]

There are some good airgun mechanics here, and before I send my rifle back to Hatsan for service, I would like to see what you guys have to say.

The rifle is brand new with only a couple of hundred pellets through it. Before I got a moderator, I took it out to the country to see how it might do at 50 yards, and what I saw made me think that this rifle can be a shooter. A couple of weeks later, when I had received a moderator and could shoot at my house, I began a chrony run to see what the rifle was doing. I ran about 40 pellets, and all was well. During the second round, however, one of the magazines began jamming and refused to advance properly. The second one seemed to be doing okay, however, so I continued. After completing the run, averaging about 800 fps with JSB 25.39 gr pellets, I decided to tighten the hammer spring a bit to get the velocity up around 900 fps. So I turned it CCW by 2 full turns. Probably too much for the initial adjustment, but I had a ways to go.

Anyway, the second magazine now refused to index properly, and I couldn't load any pellets. Hatsan Service said that the HS could be too tight and to back off a bit until the mag began working again. So I did 2 turns CW to put the spring back where it was before I began monkeying with it. Didn't help. Still cannot load a pellet.

Any thoughts as to what may be going on? In all of my research on Hatsan PCPs, I have never seen anyone speak of feeding issues, and one of the serious problems, IMHO, with Hatsan PCPs is the difficulty of loading singles.

[Bwalton]

I have never seen issues of that nature... I do round and polish my mags for a smooth rotation, when I spin it, its almost like a revolver spinning. Maybe a burr or something.

[Schmeddz1]

One works fine and the other doesn't? Compare the two closely. There is what seems to me a lot of 'flash' or defects from the casting process of the aluminum. This 'flash' can be lightly sanded off with fine sand paper. You shouldn't have to get real aggressive, just a light polish.  There have been plenty of posts that I have seen about smoothing the insides where the pellet holes are. I'm wondering if the diameters of the two might be different? Or its possible the width front to back as it sits in the gun? If you had a caliper or a micrometer to check the diameter and width of the magazines to each other, that would be best. 

That's a basic troubleshooting technique that any mechanical type uses. Comparing a bad thing to a good thing. It's a total cheat and it works really well!

Also check the center hole of the mag where the brass locking rod holds it into the gun. Are the center holes the same or have some grit or debris that prevents the mag from rotating?
A small dab of oil perhaps? I'm thinking it will be something simple. 

[GoneShootn]

One works fine and the other doesn't? Compare the two closely. There is what seems to me a lot of 'flash' or defects from the casting process of the aluminum. This 'flash' can be lightly sanded off with fine sand paper. You shouldn't have to get real aggressive, just a light polish.  There have been plenty of posts that I have seen about smoothing the insides where the pellet holes are. I'm wondering if the diameters of the two might be different? Or its possible the width front to back as it sits in the gun? If you had a caliper or a micrometer to check the diameter and width of the magazines to each other, that would be best. 

That's a basic troubleshooting technique that any mechanical type uses. Comparing a bad thing to a good thing. It's a total cheat and it works really well!

Also check the center hole of the mag where the brass locking rod holds it into the gun. Are the center holes the same or have some grit or debris that prevents the mag from rotating?
A small dab of oil perhaps? I'm thinking it will be something simple.

After the hammer spring adjustment, the second one quit working.

[Schmeddz1]

Yes. It still begs to be compared to the one that actually is working. If you had a total failure of both, I would be more likely to suspect the hammer spring adjustment as being the primary problem. Since one mag is working with no problems (Right?) then I would definitely compare the working mag to the non working mag.
Here's some photo's of the flash from casting I was talking about.

[GoneShootn]

Yes. It still begs to be compared to the one that actually is working. If you had a total failure of both, I would be more likely to suspect the hammer spring adjustment as being the primary problem. Since one mag is working with no problems (Right?) then I would definitely compare the working mag to the non working mag.
Here's some photo's of the flash from casting I was talking about.

I don't see any evidence of that sort of thing. The funny thing is that both worked flawlessly for about the first 100 pellets. That's several cycles of both mags. Then one became janky and then the other.

One thing (of many) that I do not understand is how could the hammer spring affect the magazine feeding?

[Schmeddz1]

I'm not quite familiar with the mechanism for the rotation of the mag cylinders. I have not had the rifle apart for major mods yet. (I plan on it eventually) I haven't even played with the hammer spring adjustment. I'm still learning.
There are some of those basic things I would check if it's binding, like lube, fit, and finish.
I don't have my rifle in front of me since they don't allow me to bring it to work!

[GoneShootn]

I don't have my rifle in front of me since they don't allow me to bring it to work!

I'll bet you haven't even asked.

[Schmeddz1]

I don't have my rifle in front of me since they don't allow me to bring it to work!

I'll bet you haven't even asked.

I don't dare, I work on a military base. You know how gun free zone military bases are!?!
I'm nervous even having pellets in my desk!

[pepegraves]

I never heard of that either...my magazines always index flawlessly, one of the advantages over Marauder...wish I had some insight for ya...good luck with it

[GoneShootn]

I never heard of that either...my magazines always index flawlessly, one of the advantages over Marauder...wish I had some insight for ya...good luck with it

Just one of those things. Had to happen to somebody, and I guess I'm the guy. I'm encouraged, though, that I have never seen a single mention of this kind of malfunction in Hatsans. If I had been screwing around with it, I would say that it's something I did, but, except for the HS adjustment, which was done after the problem had already begun, and removing the sights, I haven't done anything. Thanks.

[Mod90]

Look inside the slot where the mag is inserted. on the bottom of that slot there's a screw that can and does back out sometimes. when it does it causes cycling issues with the mag.

[zandrew]

Did you take the side cover off that is on the opposite side of where the magazine is installed? The first time I worked on mine I removed it is why I ask and it contains the magazine indexer. I would remove the magazine and work the mechanism several times and watch and seee if its working correctly. Its just a small finger that pushes the magazine around 1 slot.

I couldn't imagine you creating enough wear that it is now wore out.

You didn't say if this a pump action or a side lever. If it is a pump action they have to be cocked fairly hard. You can actually engage the hammer mechanism on a pump and not index the magazine. If you have a pump make sure you are pumping it all the way back.

[GoneShootn]

Did you take the side cover off that is on the opposite side of where the magazine is installed? The first time I worked on mine I removed it is why I ask and it contains the magazine indexer. I would remove the magazine and work the mechanism several times and watch and seee if its working correctly. Its just a small finger that pushes the magazine around 1 slot.

I couldn't imagine you creating enough wear that it is now wore out.

You didn't say if this a pump action or a side lever. If it is a pump action they have to be cocked fairly hard. You can actually engage the hammer mechanism on a pump and not index the magazine. If you have a pump make sure you are pumping it all the way back.

It's a side-lever, and I didn't remove the side cover. I would like to see how it works, but this early in its life, it's probably best just to send it on to Hatsan and let them take care of it, so I shipped it off today. I did ask them, though, if possible, to have their tech guy tell me what went wrong. Probably won't get that, but I would like to know.

Thanks.

[Ribbonstone]

Probably not a great big help, but its pretty simple under that cover (although there are two springs that can jump out at you).



The timing is controlled by the bands around the striker.  If the striker can't be fully compressed to the rear (too much spring tension or some other problem) OR is not allowed to go fully foirward, then the striker's bands won't "trip" the hand enough to cycle.

[GoneShootn]

Thanks for the photo. What do you suppose might cause it to not position the pellet properly? I assume that's what is happening.

[oldpro]

Were the mags easy to push into the mag slot or where they very tight? I had something similar happen to me.

[GoneShootn]

Not tight. Seemed about right.

[Ribbonstone]

Still think the spring adjustment made is keeping the striker from moving back far enough to let the hand reset and engage the "tooth" of the magazine.  Sounds like it was just barely allowing the hand to drop into reset as it was out the box.

Reverse your spring adjustment, and maybe even add 1/4 turn less, and see if that cures it.

[GoneShootn]

I had reversed the adjustment. Didn't help. I didn't do an extra 1/4 turn, however. Following that logic, though, if that were the problem, then it would mean that the hammer spring was already at max adjustment out of the box. I don't think that's correct. If it is, it shouldn't be, and, if that were the case, then Hatsan should say that the HS is already maxed out and should not be upped any more at all for to do so would render the rifle inoperable. To me, the fact is that my adjusting the HS should not have broken the gun, and, if it did, the reversal should have fixed it, and it is not my fault that it didn't.

If you are correct, and the HS needed to be backed out even more, then Hatsan could say that I caused the problem and bill me for shipping both ways plus the "repair". My impression is that they are better than that, so I guess we'll see what happens. Perhaps I'm guilty of thinking of the Hatsan like the Marauder, in that the HS is freely adjustable, and you can easily go back and forth without breaking anything. Maybe the Hatsan is more finicky and less rugged. I hope that's not the case, though. As I said, I like the rifle, and it looks as if it is going to be a good shooter. It seems apparent, though, that I am going to somehow have to learn how the action works so as to be able to repair it myself if it breaks after the warranty expires. The magazine and feeding system have to work properly because, unlike the Marauder, it is almost impossible to load these rifles manually.

Thanks for the input.