GTA

Airguns by Make and Model => Crosman Airguns => Topic started by: tennx on June 14, 2024, 07:04:32 PM

Title: Crosman 397 ?
Post by: tennx on June 14, 2024, 07:04:32 PM
I’ve taken a 392 apart but I can’t remember if there is  a transfer port sleeve .didnt see anything on schematic….or is it just a tight fit between valve and tube…my pellets have started hanging up as they enter the breech…there is no burr..it’s similar to 2240 steel breech hang up….the gun gets shot but not on a regular basis…I’ve had it since new….circa 1994..distinct click if u force the pellet home…I checked a spent pellet no apparent damage from hangin up…I can live with it ,but inquiring minds want to know and fix it…lol


Thanks
Title: Re: Crosman 397 ?
Post by: caudie on June 14, 2024, 08:37:49 PM
I've had my 392 hang on pellets entering the chamber.  I started loading a pellet in front of the bolt then holding the muzzle straight up and push the bolt home.  Never had one hang since.
Title: Re: Crosman 397 ?
Post by: tennx on June 14, 2024, 08:52:13 PM
I've had my 392 hang on pellets entering the chamber.  I started loading a pellet in front of the bolt then holding the muzzle straight up and push the bolt home.  Never had one hang since.

Yeah tried that and have done it with other guns…didnt work on this .177….

Thanks
Title: Re: Crosman 397 ?
Post by: Blowpipe Sam on June 14, 2024, 08:54:24 PM
I'se confused.  What gun is we talking about here?
Title: Re: Crosman 397 ?
Post by: tennx on June 14, 2024, 09:00:47 PM
I'se confused.  What gun is we talking about here?

Subject line says 397…Im asking about a 397..lol…I shouldnt have mentioned the 392 buts it the only one I know its innards…my bad
Title: Re: Crosman 397 ?
Post by: Blowpipe Sam on June 14, 2024, 09:22:25 PM
I recently rebuilt a Benjamin 397 and I don't remember any sort of transfer port.

Croman 362 has one though.
Title: Re: Crosman 397 ?
Post by: Back_Roads on June 15, 2024, 08:10:54 PM
 397 the barrel is soldered to the compression tube, if that solder separates then you have issues.
Title: Re: Crosman 397 ?
Post by: tennx on June 15, 2024, 08:32:18 PM
397 the barrel is soldered to the compression tube, if that solder separates then you have issues.

No separation…the issue seems to be that instead of passing over the tp . Pellets are tipping into it and I have to force them pass..just started recently…
Title: Re: Crosman 397 ?
Post by: Back_Roads on June 15, 2024, 08:58:17 PM
 Wonder if the inner stock lug screw is loose, if that would make a difference. Pull the action out of the stock and have a look see ???
https://support.crosman.com/hc/en-us/article_attachments/201592010/B397-EVP___PL4__MFD_10-07.pdf
Title: Re: Crosman 397 ?
Post by: tennx on June 15, 2024, 09:06:17 PM
Wonder if the inner stock lug screw is loose, if that would make a difference. Pull the action out of the stock and have a look see ???
https://support.crosman.com/hc/en-us/article_attachments/201592010/B397-EVP___PL4__MFD_10-07.pdf

Will check…. Just a fyi I found some daisy precision max pointed pellets and they load with almost no resistance…Ive tried all the round nose stock and wad cutters…I got …they all hang to some degree….

Thanks
Title: Re: Crosman 397 ?
Post by: RBQChicken on June 15, 2024, 10:45:37 PM
397 the barrel is soldered to the compression tube, if that solder separates then you have issues.
No separation…the issue seems to be that instead of passing over the tp . Pellets are tipping into it and I have to force them pass..just started recently…
I don't think your pellet is getting tripped up by the transfer port. I think it's getting tripped up where the breech area (where you load the pellet) meets the beginning of the barrel. The transition from breech to barrel is not a nice, smooth taper (as it should be), but rather an abrupt transition, which results in a bit of a ledge for softer pellets to get hung up on.  The harder pellets with rounded noses just slide up over the ledge without getting caught.

Take the back end of the gun off so you can remove the bolt and get at the area in question.  Get a foot-long or so piece of wooden doweling just small enough to fit in the breach. Taper one end of it and then cut a slit in the end to hold some sandpaper (220 would be fine).  Fit it in place on the dowel (press it in place so it conforms to the cone shape you formed on the end of the dowel) and shove it in until you are just up to the ledge where breech meets barrel.  It’s just past the transfer port.

It doesn’t take much to wear that edge down to a smooth taper.  Several twists one way and then the other.  The brass sands away much easier than steel.

Fold the sandpaper in half before you install it on the dowel.  That way you’ll have sandy sides on both sides of the paper.  It helps when you’re reversing direction while sanding.

I've found that doing this makes the gun shoot a greater variety of pellets accurately. I assume it's because you are no longer tearing up the pellets while loading.

I would have posted links to the articles where I learned about this process (all here on GTA), but I'll be darned if I can find them, even though I had them bookmarked.  The joys of getting senile.
Hope this helps!
Title: Re: Crosman 397 ?
Post by: tennx on June 15, 2024, 11:00:46 PM
397 the barrel is soldered to the compression tube, if that solder separates then you have issues.
No separation…the issue seems to be that instead of passing over the tp . Pellets are tipping into it and I have to force them pass..just started recently…
I don't think your pellet is getting tripped up by the transfer port. I think it's getting tripped up where the breech area (where you load the pellet) meets the beginning of the barrel. The transition from breech to barrel is not a nice, smooth taper (as it should be), but rather an abrupt transition, which results in a bit of a ledge for softer pellets to get hung up on.  The harder pellets with rounded noses just slide up over the ledge without getting caught.

Take the back end of the gun off so you can remove the bolt and get at the area in question.  Get a foot-long or so piece of wooden doweling just small enough to fit in the breach. Taper one end of it and then cut a slit in the end to hold some sandpaper (220 would be fine).  Fit it in place on the dowel (press it in place so it conforms to the cone shape you formed on the end of the dowel) and shove it in until you are just up to the ledge where breech meets barrel.  It’s just past the transfer port.

It doesn’t take much to wear that edge down to a smooth taper.  Several twists one way and then the other.  The brass sands away much easier than steel.

Fold the sandpaper in half before you install it on the dowel.  That way you’ll have sandy sides on both sides of the paper.  It helps when you’re reversing direction while sanding.

I've found that doing this makes the gun shoot a greater variety of pellets accurately. I assume it's because you are no longer tearing up the pellets while loading.

I would have posted links to the articles where I learned about this process (all here on GTA), but I'll be darned if I can find them, even though I had them bookmarked.  The joys of getting senile.
Hope this helps!

What your saying makes sense and not to argue…I can see the barrel edge and the round nose pellet passes smoothly over it…then stops…actually the pellet stops 3 times right after entry then as u proceed stops again and the 3rd stop takes some effort to finish loading….not a good explanation and I dont have anything to video it…I will sand it ,certainly willing to try…but not much room..lol

Whatever the problem is,doesn't affect accuracy

Thanks
Title: Re: Crosman 397 ?
Post by: Back_Roads on June 16, 2024, 08:06:04 AM
 Hmm when working the bolt without a pellet do you feel some or all of  the same resistance, just thinking could be the bolt tension ???
Title: Re: Crosman 397 ?
Post by: tennx on June 16, 2024, 08:13:43 AM
Hmm when working the bolt without a pellet do you feel some or all of  the same resistance, just thinking could be the bolt tension ???

Bolt functions as u would expect….
Title: Re: Crosman 397 ?
Post by: TerryM on June 16, 2024, 10:12:56 AM
I have noticed some pellets feed smoothly while others take some effort to chamber.  I assumed it was due to different head diameter's.
Title: Re: Crosman 397 ?
Post by: tennx on June 16, 2024, 11:29:57 AM
Occasionally I get a pellet needing to be removed from a gun…I use a metal coat hangar with tape on the end…I cant remember if I had done this to this gun and maybe buggered up the inside…as I said all pellets are a hard fit…except the pointed …may have to go to them for the times I shoot the gun…
Title: Re: Crosman 397 ?
Post by: avator on June 16, 2024, 11:38:05 AM
I use a .177 brass cleaning rod to remove stuck pellets no matter the caliber.
Sounds like there is a burr in there.  ?  Any chance of getting a look with a bore scope?
https://a.co/d/70D02WF
Title: Re: Crosman 397 ?
Post by: tennx on June 16, 2024, 12:06:44 PM
I use a .177 brass cleaning rod to remove stuck pellets no matter the caliber.
Sounds like there is a burr in there.  ?  Any chance of getting a look with a bore scope?
https://a.co/d/70D02WF

I looked at the ones that use your IPhone…might give it a try…just bumfuzzles me as to why all of a sudden…lol