Benjamin 392 Pivot roll pin

[BarnBoy]

Hey,
I recently bought a Benjamin 392 and when it came out of the box the roll pin was not in all the way. After putting a 100 or so rounds through it I notice it has started to walk out a bit. So I tapped it in again, then after a while it walks out again. Whats the best way to fix this? I don't want to send it back to Crosman to be repaired. I was thinking maybe trying to spread it on one end a little, then drive it in. I should be careful though, banging on it right?

Thanks

[tennx]

Smarter guys than me will be along...but I used this on my 1322 pivot and I see they make them for Sheridan/maybe Benjis..... ...  good luck

http://mellonair.myfreesites.net/solid-pins

Also...
http://www.alchemyairwerks.com/

[longhunter]

mellon's pin for the Sheridan will fit the Benjamin, also. you could call david at alchemy, and ask him to make you one. I think his would look much nicer.

[ev-in-az]

mellon's pin for the Sheridan will fit the Benjamin, also. you could call david at alchemy, and ask him to make you one. I think his would look much nicer.

+1 Mellon's solid pins work great.

[bbv13]

I've never had one walk out. The first thing I would try is a new roll pin from the hardware store. It's hard to imagine the hole in the pump arm being out of round or damaged on a new gun but I guess it could happen if they drove the roll pin in crooked at the factory? I think a bent roll pin would cause it to walk too. You can take the front end of the gun apart pretty easily and the problem may become obvious when you do.

Bryan

[BarnBoy]

Thanks for the replies. I don't really want to buy another one yet. It seems like to me the one end is a little larger then the other, because when I tap it in, it goes in so far then stops. Hope that makes sense. It should go in a 1/16th or so more. The pin is straight as far as I can tell. I am thinking it was either not driven in all the way from the factory, or maybe came loose it shipping (unlikely but maybe), or there is something up with the roll pin itself. I am going to try and open the pump handle to relieve pressure, then carefully support the gun on either side of the hole, and then try to carefully tap the roll pin in all the way. If it stays, then I will forget about it, otherwise I will get a new pin from the hardware store. Does anyone know what size it is?

Again, thanks for the help.

[longhunter]

3/16 x 1 inch.

[BarnBoy]

Thanks Longhunter. Will let you know how it goes.

[aceflier]

Just put one in my 72 dan 3/16x1inch is correct. I use a tapered nail punch on each end to make sure I don't loose this one. Only $.30 each so I got half a dozen.

[BarnBoy]

Ok, so, I tapped it in all the way, and no go. Started walking out after 20 rds. So I took the pin out. I figured it was spring steel but thought I might be able to make it spread a little on one end. Nope, that stuff is called spring steel for a reason. So, I will probably get a 3/16 by 1 inch pin from the hardware store and try that. The yoke on either side had nice holes, didn't look out of round to me. The metal pump arm hole was good too. Do you think a new pin would be just as loose or be tight? Actually, I just thought of this. Would a 1 inch section of 3/16 steel round bar work? I could roughen it up a bit so it would grab if it was a little small.

 And aceflier, what do you mean by a nail punch on each end? I am thinking something wedged in the hole of the roll pin to spread it and let it grab, and not spin or move?

[TerryM]

  Sounds to me like a defective roll pin, slightly undersize.  A properly fitting pin will be quite tight.

  Dealing with these roll pins is my least favorite part of taking an airgun apart.  The first few times I did it, I found it a little unnerving, whacking at my gun with a hammer and punch.  Still do, actually.  I use a rawhide mallet so there is not as much shock involved as with a steel hammer.  Make sure and use a proper size, flat end punch.  I rest the tube on a wood block padded with a towel.

[BarnBoy]

Ok, thanks a lot. I will try a new pin then before I do anything. Otherwise, could it be a slightly oversize hole?

I know! I hate whacking them like that with a hammer. I rested mine on a block of wood with a thin foam sheet for protection. Hehe, well, when I took it out I went the redneck way and used the right size nail, with the end clipped off and filed round so there were no sharp edges. Maybe not the best, but I was real careful and it didn't appear to damage anything. I think that since it wasn't too tight it didn't matter as much. Though, when I reassemble I will get a 3/16 flat end punch.

[aceflier]

I use 2 hammers and tap one end with the punch then put it in. Then set the rifle with pin on another hammer while in its spot. Pin only! And tap the other end wider. It won't work out after that. Getting it back out is a bit harder to do but with some good pliers and a towel it's not hard to squeeze it back to normal.

[bbv13]

When removing or installing a roll pin be sure to support it on both sides close to the hole so the pressure can't be put on the barrel or tube.

Buy yourself a punch set from Lowes or Home Depot. It's not complicated but feeling comfortable hitting it hard enough requires doing it a few times.

Bryan

[Rob112o]

After, I buy a rifle be it new or vintage. When I remove those roll pins I never put them back in. I go to the hardware store and go to the drawer section. Get the 1" x 3/16" steel dowel pins and 4 c-clips. Boom, dunzo!! Problem solved and you don't have to worry about making that hole slightly bigger every time you bash those roll pins in and out. I think it looks better also, but that my opinion. Lastly, those roll pins are a haven/magnet for gunk, lint, and other pieces of matter. Which I feel eventually makes their way into the air tube when you oil that location.

[mentolio]

Before installing the pin, I take it to the belt sander and just lightly chamfer one end (almost creating a point, or ramp along one edge). This makes it easier for the pin to compress and enter the hole, and to self center where needed.

[longhunter]

After, I buy a rifle be it new or vintage. When I remove those roll pins I never put them back in. I go to the hardware store and go to the drawer section. Get the 1" x 3/16" steel dowel pins and 4 c-clips. Boom, dunzo!! Problem solved and you don't have to worry about making that hole slightly bigger every time you bash those roll pins in and out. I think it looks better also, but that my opinion. Lastly, those roll pins are a haven/magnet for gunk, lint, and other pieces of matter. Which I feel eventually makes their way into the air tube when you oil that location.

hey Rob, are those pins already grooved for the c-clip, or, do you make the grooves yourself??

[BarnBoy]

Rob, that a good idea. How do you groove it? Dremel with thin cut-off wheel?

And I will chamfer the one end if I go the roll pin route.

I made sure to support both sides, so there was minimal pressure on the tube.

I plan on getting a cheap punch or punch set for the re-install.

Thanks for all the ideas.

[tennx]

Rob, that a good idea. How do you groove it? Dremel with thin cut-off wheel?

And I will chamfer the one end if I go the roll pin route.

I made sure to support both sides, so there was minimal pressure on the tube.

I plan on getting a cheap punch or punch set for the re-install.

Thanks for all the ideas.

I got my punch set at Harbor Freight $9 ....  ...good luck

[robertr]

You could try some cylindrical sealant on the pin, works the same as locktite for screws. http://www.loctite.com.au/3320_AUE_HTML.htm?nodeid=8802648195073