Benjamin marauder barrel help

a Pellet shouldn’t be hard to push. A slug could be way different.

Raden,

It is relatively normal for the pellet to be tight, I believe that the newer design barrels are not choked, I'm not sure, but I can find out for you in a day or 2, I'm working with Crosmans barrel engineer to help develop better, more consistent barrels.

That being said, Crosman depends on a tight fit of their pellets in their barrels for an air seal, unlike other diabolo pellets. Most pellet manufacturers depend on a thin skirt to blow out to make a proper seal.

Just make sure the implement that you use does not have any sharp edges on it to damage the barrel. If you use a multi piece cleaning rod, please tape the joints to avoid damage.

Hope this helps 

Tom Holland 

Field Target Tech 

A typical diabolo pellet should go through the choke without much difficulty. If you've tried 2 or 3 different types of pellets and they are all taking more than 5 pounds of force, something is awry.

A cylindrical slug like an H&N Rabbit Magnum would be a different story.

If you can get a decent macro photo of the pellets you've pushed through, that would be very telling.

Raden, 

That is a lot of force.

Consider this. When I push a pellet/slug through a barrel, and it's a bit tough, this is what I do. I put the cleaning rod handle on the floor, and use the barrel as a slide hammer. I pull the barrel up a foot or so, and with moderate force, slam it downwards. Sometimes I have to do that a few times.

What kind of pellet got stuck? If it's a Crosman pellet, it would be that hard. If it's a skirted pellet, it should be a lot less, but still a little bit of force will be needed. A Crosman pellet will fit extremely tight, and that would explain a lot, if it is that hard.

Crosman barrels are MUCH smaller in diameter in the lands as well as the grooves compared to other barrel manufacturers. They can be, depending on when made, up to 6 thousandths smaller. I spoke to Crosmans barrel engineer this afternoon at the Crosman All American Field Target Championship, and I was amazed and in awe when he told me the barrel dimensions. Much smaller than the other manufacturers by far.

Is it possible to get a picture of the metal deformation that you mentioned? I would be interested in what it looks like, I would like to think you did not do any damage to it. If the other barrel was the same, it could be a manufacturing defect. I'd be curious.

Tom Holland 

Field Target Tech 

Is the barrel removed from the action?

Raden, 

As I said, the Crosman pellets should fit that much tighter, it's the nature of the beast. Crosman manufacturers their barrels to accommodate THIER pellets, all others are thrown by the wayside. If other pellets work better, or have characteristics that work better, it's important to remember that they are making these barrels in accordance to their pellets, no one else's. 

Tom Holland 

Field Target Tech 

Raden, 

It's perfectly normal to have Crosman pellets fit EXTREMELY tight in a Crosman barrel. As I said, that's how they depend on their accuracy due to their tight fit......perfectly normal 

FYI, I just grabbed a .22 Marauder barrel and pushed through a couple of pellets. A Crosman Premier Hollow Point needed about 5 lbs of force to move through the choke. A JSB 18.1gr needed about 3 lbs.

You estimated it took >100lbs to get a Crosman pellet through the replacement barrel. That's not tight. That says there is something wrong.

Let's do some math ....

assuming the pressure in the barrel = 2000 pounds per sq inch

cross section area of the bore of a .22 barrel = 0.037 sq inch

force on the pellet = pressure x area = 2000 x 0.037 = 74 pounds

If it takes 145 to 160 pound force to push the pellet out, there is no way that it can be shot out of the barrel unless the pressure is super high 

Very interesting discussion.

I can't say I've shot a crosman pellet through a Mrod barrel since Gen 1 days. I probably have never pushed one through with rod, either. The 14.3 crosmans never shot well in my Mrods back then, and weren't really heavy enough for pcp work. The new 19g were probably developed for the Mrod, but haven't tried that either. Back then, it was Barracuda Match in 5.53 head size, that seemed to work the best. 

The 22 barrels in Gen 2 were better and JSB's shot well. But, never tried any crosman pellets. My 22 mrod barrels are all LW now. 

I have not had any of the latest design 22 crosman barrels. Not sure if you would get one with the old part number. FWIW: I do believe they are all coming with a choke, contrary to what was posted in the CS under barrel info. 

Raden,

I had a Lothar Walther barrel on mine, and to be honest, the Crosman barrel shot better. LW barrels are a little picky when it comes to pellets, the Crosman barrels are not, they'll eat anything well.

If you remove your barrel, and if you have a lathe, you can recrown and/or refinish it. If you do not have a lathe, here's what you can do.

Clamp the barrel onto something solid, where the muzzle is easily accessible. Take a power drill and chuck an 8-32 or 8-24 BRASS screw into the drill, with the head sticking out. I emphasize brass, because if you use zinc or steel, you will ruin the barrel. Put some polishing compound on the head of the screw, and push it onto the end of the barrel, and turn the drill on. Medium speed will do. Wiggle it in a circular motion all around, with light pressure. Do this for a minute or so. Then, put the drill in reverse and do the same thing. Clean it off and inspect it. You should be able to clearly see the lands and grooves. Repeat if necessary. That's all there is to cleaning up crown that needs a little help to make it a better shooter.

Tom Holland 

Field Target Tech 

Raden,

I also forgot to mention that you have to make sure that you clean the barrel well after using the grinding compound, as any residual compound could stay in there abrading the barrel further than what you need. Also, after the crown cleanup that I mentioned above, you should do the same thing.

Tom Holland 

Field Target Tech 

Does anyone know where I can find lw barrels? I know i can buy a blank and have someone machine one but is there anywhere else I can pick one up? If not ill wait about a year for crosman to start selling them. They told me themselves that they will have them in less than a year.

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Last I knew, Roy at Mountain Air was selling 177 and 22 LW barrels for Mrod. Around $200. I'm glad crosman has said they will sell the LW barrel, they will probably be almost half of that. ie the Challenger LW barrel is around $90.

I can't say that LW are pellet picky or not. They shot JSB/AA well, so didn't ever go searching further. On the other hand, my older crosman barrels that were accurate, seemed to be pellet picky, with specific head size pellets. Different experiences.

Unfortunately, old or new barrels, it seems that crosman QC could improve. Burrs and crown issues have been common in all. And your experience, shows that even the latest process, hasn't cured that. You would think they could come up with a laser inspection that could catch most/all of those issues. 

Anyway, glad you got it shooting better. Save that $200 for another day.