Benjamin barrel swap?

[bgolden84]

I currently have a Benjamin titan gp in. 22  I am waiting for my Benjamin trail np in .177 to arrive. Is it possible to swap the. 22 barrel from the titan to the trail np to have some options?

[bgolden84]

OK I found my answer.  The search feature is awesome.  Sorry I'm I'm new to the whole forum thing.  Is there any lost velocity or accuracy going from . 177 to . 22? My old titan gp has some issues I think K the seal has gone bad in it.  It's all over as far as the accuracy and possibly the velocity but I don't have a chronograph to verify. 

[HYspd]

is the barrel pivot bolt adjusted?

[bgolden84]

is the barrel pivot bolt adjusted?

I'm not sure.  I know it's tight but I don't think there is anything to adjust.  If there is how do I go about adjusting It?

[JR]

Short of tearing the gun apart and checking the piston seal you can check to make sure the breach seal sticks out a little for a good seal. The barrel pivot joint should not have any side to side play, check the plastic washers and snug the screw up a little is needed. Just don't get to carried away cranking on the screw, good and snug to tight, if you crank on it for all your worth it could break or damage the screw.

I bought a 177 barrel for my Regal/Trail, along with cocking linkage, pins, seal, etc. I made a complete swap barrel assembly, remove the pivot screw, swap between 177 and 22 in 10 minutes or less. The gun started out as a Benjamin Regal 22 cal., I swapped in a Trail TH wood stock and main tube so I could have a Weaver rail.  I just got a used Trail XL 1100 from a GTA member a that I ordered a 25 cal. barrel and the rest of the parts for, so I can swap calibers. I have all the parts for the XL but no pellets so I'll have to wait for another week to try it.

[Roadworthy]

In answer to one of your earlier questions, you will lose velocity when you switch from .177 to .22.  You are using the same power plant to push a larger pellet down a larger diameter barrel.

Will you lose accuracy?  Not necessarily but you do have to bear in mind the .177 does have a flatter trajectory than the .22.

[HYspd]

you're using the same power plant to shoot a HEAVIER pellet...

like weight pellets in both calibers will shoot at similar velocities...

[bgolden84]

Thanks for all the insight.  What about opening up the port just a little would that help or hurt? I'd imagine it would hurt

[56S]

Thanks for all the insight.  What about opening up the port just a little would that help or hurt? I'd imagine it would hurt

The Jury is still out on opening up the transfer port.  IIRC, many of the Crosman/Benjamin break barrel rifles share the same compression tube, piston and gas strut within model lines regrdless of calibers.  Saying that, the transfer port diameter may be the same for a .177 , .22 and a .25.
With all the talk about pellets being too light or too heavy hurting the powerplant, I started to really get confused.  Why could the same powerplant shoot a 7.9gr pellet in .177 and a 14.3 in a .22?  One reason may be the diameter of the bore and the resultant force behind the pellet.

Regardless, on transfer port diameter, Some time ago I noticed my .22 Titan had a ragged & rough looking inside diameter port.  .123" I believe.  I opened it up to .138" thinking I would set up the chronograph and prove that I had created a "Super Titan".  Well, I never did make it.  FPS was just about the same.  It's hard to do a scientific experiment when you also change the type of lube used at the same time you open the port.
What I did find was a smoother shooting rifle and one that had never shot better.  My 1" spinner targets at set up about 25yds from my front porch and I was popping them one after the other just using a handrailing as a rest, sitting in a lawn chair.  A hunter's rest I call it.
But, on the flip side at 4,500+- shots I started to lose velocity.  Right now I down to the 680s instead of the 740s.  I am seeing a slight oil stain on my piston so maybe opening up the port did my piston no favors?  I'll never know.  Hey, 4,500 shots on a powerplant isn't bad.  Some springers break a spring before that many shots.
I am curious what the diameter of the transfer port is on your regal/trail compaired to the Titan.

[bgolden84]

With out getting a set of dial calipers the port on . 177 trail looks to be smaller than the port on the. 22 titan.  This is just a naked eye comparison.  The port on the titan does not look very good it's kind of oblong.  The trail port is fairly round.  I've had 3 Piston powered air rifles in the last week.  The first is the titan GP second was a gamo bone collector bull whisper in. 177 and last and my favorite is the trail NP all weather in. 177.  The gamo was returned twice due to poor quality.  It was spitting scope rings off on both of the rifles.  The second one had a stripped out breach screw and the rubber grip panel on the left side up front kept falling off when  cocking it.  I do like the trigger on the gamo far better but I can take care of that on my own.  The trail NP is a dream to shoot.   Quite accurate and low recoil.  The titan GP is all over the map with accuracy and destroyed every scope I've put on it.  The titan does  not diesel at all.  I am still breaking in the trail NP.  I cleaned it up when I got it home.  But so far for the money it looks like the trail NP is where  at. 

[JR]

Looking at the parts breakdown for the Trail and the Regal the compression tube is the same part number for both 177 and 22. I might have access to pin hole ID measuring tools, if I can I'll check a couple guns and see what they read. I don't know but I would assume there is a optimal hole size range vs the chamber volume, to much math for me.

[bgolden84]

Well I decided to dive in and disassemble the titan gp.  I figured out the problem.  The seal for the gas ram is horrid. It has nicks and looks like some one went after it with a pocket knife.  I am going to order the seal and so how it does.  One question I have is have you guys ever heard of a clp called froglube.? I use it on all of my powder burners and it's great.  It's all organic and not petroleum based.  I have no  idea if it's wise to use in the air rifle  don't think it's combustible.

[JR]

I have used it on my AR15, not a good lube for the chamber and seal. Froglube is kinda the poormans self applied Teflon coating is the theory. Works ok for loose fitting metal to metal sliding action, not so good as a sealing and lube. I have tried Krytox and it did ok but it's $60 for 2oz's, just easier for the average joe to stay with the tried and proved Moly grease.

[bgolden84]

I'm learning a lot from you all.  I tore the entire gun apart.  Trigger and all.  I found the bad seal and there was oil and lots and lots of it  I cleaned everything up and used frog lube to go back together.    very impatient I decided to try a redneck fix on my seal. I used a small zip tie cut to length to push in the lip of the seal.  It opens it up enough that it seals perfect and sounds like the pressure is back where it should be.  As a side note frog lube is loud lol.  First shot let off a lot of spray.  Second shot was normal third sounded like a 22mag. I'm not playing with it anymore as I don't
want the police to show up.   I'll do some shooting tomorrow and report back.   Once I figure out how to get some pictures on  I'll show you guys what I found d and what I did to fix it. 

[Roadworthy]

Just because Frog Luge is not petroleum based does not mean it won't diesel.  There are non-petroleum lubes that burn nicely.  Have you ever heard of bio-diesel?  It's not petroleum but it burns.  Why is that?  According to legend, when Ferdinand Diesel unveiled his engine it ran on vegetable oil.  The petroleum have simply refined petroleum to a similar stage.

Back to the Frog Lube.  It has been suspected it may be fish oil and some other stuff in the compound.  It is a good external for rust prevention.  I would not use it inside a gun.

[HYspd]

that's an excellent example of what not to do to an Airgun..


high molly content grease on the seal and very very little of it..
just enough to wet the bore where the seal runs..


stuffing the piston is just gonna tear up the bore especially once it spit outs
the zip tie shimming

[bgolden84]

Well after some extremely loud and hot shots this morning I tore it all back down and honed the compression chamber and lubed it very sparingly with some molly grease.  The first few shots where loud but it quieted down a lot.  It's far more consistent and groups of. 50" @25 yards.  The zip tie was an experiment and will get tossed when my new seal gets here.  I'm going to order a couple seals for the titan and the trail.  I'm also thinking of changing out the compression tube for one like the trail.  I hate the 11mm dove tail.  I much prefer the Weaver style base it holds zero on all my scopes.