.25 Marauder - Bolt is difficult to operate

[Sqrl Klr]

I'll be getting a larger hammer made to try and solve the issue since the bolt screw does not cause it in my case.

[Sqrl Klr]

I have a bnm breech on my disco which came with no sleeve between the bolt and screw.

[bnowlin]

Sorry please remove

[Sqrl Klr]

No worries. On both since I'm having the same problem. Mine is part mrod at this point anyway I guess with the mrod items on my disco. A disco/mrod hybrid if you will. hehe

[rjorge]

I have a bnm breech on my disco which came with no sleeve between the bolt and screw.

I have a BNM breech as well, and right now I am having the same problem.
Using a long set screw to engage the hammer pin is not a good idea. Overtime the threads of the set screw will gouge the inside of the breech and shavings can get in the bolt area and jam the bolt (happened to me), so I made a new screw to replace the set screw and it helped. It eliminated the side to side play of the bolt and gave a more positive contact with the pin on the hammer.
Now that I am using an even heavier spring it is really bad. It is even worse on a new Don C. SS hammer and 2260 PCP tube that has a rough inside surface finish. This along with the bolt forcing the back of the hammer down and the front of the hammer up makes it impossible to cock the gun. I have tried sanding and polishing the inside of the tube and hammer. it helped very little.
Now I am working on a way to make the contact between the bolt and hammer pin as parallel as possible, which I believe will solve the problem. Or make a new hammer with closer tolerances might help as well. Patiently waiting on my new Sherline lathe to arrive.

[Sqrl Klr]

Well rj if the larger hammer works for me I'll definitely post about it here so you can try that as well. The threads of the screw shouldn't be touching the breech since the screw's head OD is larger than the threads. I have scrapes on the breech guide rails from the screw head scraping against them which has given me shavings. As for the tube I wonder if the inside can be cerakoted. If so then that may make the tube's surface more smooth for the hammer to glide on. 

[rjorge]

Sergio shipped mine with a set screw instead of a socket head screw. I am glad he is doing that now.
I have some Durabake and I wonder if it is the same as Cerakote?

[melvin]

I had that problem with mine when I first got it and found out the problem was the "cocking lug" on the left side of the receiver.  The lug kept loosening and it would make the bolt darn near impossible to operate.  It may not be whats wrong with your rifle but it was driving me crazy on mine.  Harry (only1Harry) was having the same problem with his. 

Jeff

Thank you all for your helpful suggestions. 

The little allen head socket screw (#27 on the Benjamin Marauder exploded view parts list from Crosman) that screws into the front part of the bolt had backed out and become loose.  A bit of loc-tite, tightened the screw back up.  The rifle is shooting like butter now.

Thanks for the help.  Being new to PCP's, it is nice to know that there is a resevoir of knowledge and experience out there to help a newbie.

TR

I was going to suggest that but it looks like you figured it out.  Marauders come very poorly put together.  If you dont tighten everything it will all rattle loose.  Other then that good guns.

Ken

[TR]

After this experience, I think I will take my nice new marauder and give it a full dissassembly.  that way I'll know that everything is tight and secure.  I'll also be able to visualize the channel where the bolt screw engages the hammer to see if there is any damage there.

TR

[aack73]

yea and use lloyd-ss method. patience and pay carefull attention to the moving parts etc.

[only1harry]

TR same here, hence the bolt rash as pictured in my first post.

Jeff did Harry get that issue fixed or is he still having problems?

The 'cocking lug' on the left side of my .25 Mrod was very slightly loose when I first got it, and 10 days later I had to tighten it again for the 2nd time, after Jeff told me his was loose when he got his brand new .25.  I am thinking Loctite now.  The cocking gets maybe 10% better after tightening this screw, but I still think it's hard to cock it back, and it's always making "crunchy" noises when driving the bolt back, which many have told me is "normal".  I do not have another Marauder to compare so I just live with it and accept it. 

It 's not as hard to cock as yours, and it does not leave me with any marks, but I think it should be cocking smoother, and a little easier.  All I have to compare it to is my 3 AF Condors that cock like butter and with ease (1 finger), and my RWS/Hammerli 850 which cocks smoothly too.  With my .25 Mrod it is not a seemless movement back with the bolt.  Mine requires more strength half way back, almost like it's snagging on something.  It's probably burrs and such as Lloyd explained, and poor QA I guess, or an issue in the manufacturing process or tolerances, the way they make these parts, which could be stamping them out.  Wouldn't it be nice if all the parts were CNC machined?

[Sqrl Klr]

I firmly believe it's the part design and tolerances that should be improved where customers don't have to do it themselves and go through months of aggravation with their products. I'm not too impressed with Crosman at this point.

[Motorhead]

Same thing here with my .22 ... tho have massaged parts to get em sliding smoother and now we are cocking satisfactory.

*BOTH Screw in hammer and Screw in bolt have had the rough O.D. of there socket heads smoothed out & polished .
*Slot within hammer area of main tube hammer screw above slides within DEBURRED and polished along the edges.
*Cocking bolt polished on it's O.D. where in contact with receiver.
*Back end of hammers I.D. cleaned and polished.
*Hammer spring pre-load collar that runs within springs I.D. polished.

Gun cocks SUBSTANTIALLY smoother now.

[lloyd-ss]

Same thing here with my .22 ... tho have massaged parts to get em sliding smoother and now we are cocking satisfactory.

*BOTH Screw in hammer and Screw in bolt have had the rough O.D. of there socket heads smoothed out & polished .
*Slot within hammer area of main tube hammer screw above slides within DEBURRED and polished along the edges.
*Cocking bolt polished on it's O.D. where in contact with receiver.
*Back end of hammers I.D. cleaned and polished.
*Hammer spring pre-load collar that runs within springs I.D. polished.

Gun cocks SUBSTANTIALLY smoother now.

I think you have just described a few of the things that make the difference between a $300 gun and a $700 gun.  Good work.
Lloyd-ss

[only1harry]

I firmly believe it's the part design and tolerances that should be improved where customers don't have to do it themselves and go through months of aggravation with their products. I'm not too impressed with Crosman at this point.

I was never too impressed with Crosman   They put out cheap/average guns and that's it.  Most of their guns need work right out of the box, or will need work or mods soon down the road.  Look at the Disco.  I have read maybe 200-300 new topics on the GTA over the years, about the bolt snaping out of place when shooting, and not staying closed/locked.  Crosman still has NOT fixed this problem 4.5yrs after the 1st Disco came out.  Definitely a design issue and parts (selection) issue, but it looks like once they make a product that sells, they don't try to improve it, and that's wrong.  They only improved their latest $2K PCP because noone was buying it.  But because they sell so many $200-450 Disco & Marauders, they think everything is fine, and there is no need to fix defects or improve anything.  If it weren't for airgun forums where people go to learn how to fix these guns or defects themselves, Crosman would be getting 50-100X more returns for warranty repair.  They are lucky we have the Internet and ease of information exchange.  Without that, they would have to hire more staff to fix them, or there would be a 4-6 month waiting period to get your Mrod back from repair.

[bnowlin]

 sorry no post.Bob

[TR]

Today I installed a hammer debounce device on my Marauder.  While taking it apart, I can see the mechanics of my "bolt hard to operate" problem.

The cap screw that fastens to the left front side of the bolt (visible in the little cutout on the left of the receiver area, just behind the breech) had worked it way loose and backed itself out a little bit.  When I tried to cock the bolt, the increased length of the cap screw would put pressure down on the front of the hammer, causing the hammer to bind in its raceway.  The more it loosened up, the worse my problem got.  After tightening up this screw, the bolt worked just fine.

Fortunately, I noted no metal shavings or wear marks in the internals of the marauder (Whew...)

The lesson learned here for me is to go through and tighten up all the fasteners on a new rifle.  You never know...

TR