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Bogus Ben 132 Reseal Experience

July 19 2017 at 10:57 PM
Fred S.  (Login Insmeister)
Group #188948

 
At my advanced age, I want maximum benefit out of my personal out-put. With 10 pumps of effort, I was getting only 385fps from my Benjamin 132. I was thinking it should be more. So I decided to do a reseal. Results were disappointing. It is now doing only 370 fps while dumping 99.9%. Holds air forever. Anyone have an idea of what the reason might be for the lackluster performance?

Regards,

Fred S.

 
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Johnny366
(Login johnny366)
Group #188948

Fred did you

July 20 2017, 2:13 AM 

replace the pump cup and also adjust it so it had zero headspace? I don't have a lot of experience with the 132 but I do with the benji rifle, sheridan rifles, and crosman rifles that had the adjustable pump rod and it makes a lot of difference on these to get it adjusted right. If the pump arm falls down after shooting it is a good sign it is not adjusted right. I adjust mine to when the pump arm (about 1/4 to 1/2 inch) nearly closes just before you close it bottoms out so you have to give it that little extra push to close the pump arm. this gives it little to no headspace and also after firing the pump arm stays closed.

 
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Fred S.
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Group #188948

Yes and Yes

July 20 2017, 11:39 AM 

I did adjust the pump rod for zero head space. The cup itself seems to be "tip-top" and produces much compression. I am wondering if the position of the ports on the valve body are detrimental?

Thanks for your input Johnny.

Regards,

Fred S.

 
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James V
(Login kimo57)
Group #188948

Just recently rebuilt 8 132/137 Benji pistols

July 20 2017, 12:10 PM 

All of them will hold air over night but they do not shoot the same. Some would have a louder pop, while others do not. Even though new seals & a new pump rod seal was installed. I would adjust pump rod for minimum head space. You can't over do it though, because of the air bleed hole. If you cover the hole, not as much air would be allowed in on the pump stroke. The pump cup/rod on these pistols was not a good design. O-ring pump heads I think would work better.
Also sometimes they would leak between the rod tube & air chamber tube. That is when I have to resolder them.
Your stock should not be made of only walnut.

 
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Fred S.
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Group #188948

Ben 132 reseal

July 21 2017, 12:26 AM 

I adjusted the pump rod up to the point of the air intake hole so I think there is no more to be gained with further adjustment. I am certain there are no leaks in the joint between the 2 tubes.

James, I appreciate your input.

Fred S.

 
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DT Fletcher
(Login DTFletcher)
Group #188948

Re: Bogus Ben 132 Reseal Experience

July 20 2017, 8:43 AM 

Benjamin can be tough critters to get working right. I would suggest sending it to an expert, eg MAC-1. You might even want to have them pour a little of their steroid magic into it.

 
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Fred S.
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Group #188948

Not Ready for the White Flag

July 20 2017, 11:45 AM 

MAC-1 is the ultimate authority on pumpers but let me have my fun first. I am a tinkerer at heart. But good to know there is help out there when all else fails.

Regards,

Fred S.

 
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DT Fletcher
(Login DTFletcher)
Group #188948

Re: Not Ready for the White Flag

July 21 2017, 7:30 AM 

One of the first things I would consider would be the breech bolt. As I recall, there is no o-ring on the standard bolt and with any wear there is likely to be some blow-by. The way I test is to put hand over the breech area when firing. If any air is blowing by it's usually pretty easy to feel.

I am not aware of any aftermarket replacement bolt that include an o-ring for this model but that doesn't mean they don't exist.

 
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dave
(Login arathol1)
Group #188948

lackluster performance?

July 20 2017, 6:15 PM 

What exactly did you expect out of it? Those were never a real powerful pistol even when new. 385 fps with a 14.7 gr pellet sounds about right.
[linked image]



    
This message has been edited by arathol1 on Jul 20, 2017 6:17 PM


 
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Fred S.
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Group #188948

Performance Expectations

July 20 2017, 7:07 PM 

I had no exact expectation but did have some approximations. My 232 does over 440 fps which is close to the claim by the factory of 450. Benjamin claimed 500 for the 132. Though that seems high to me I was thinking mid 400's with a full charge.
Dave, thanks for your interest in my project.

Fred S.

 
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dave
(Login arathol1)
Group #188948

no, actually

July 20 2017, 8:19 PM 

the claim in the ad copy (which included all three versions) says "up to 500 fps". I think you will find that the 500 number is for the .177 cal 137. 385 with 14.7s is actually pretty good for that pistol.
[linked image]


 
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Fred S.
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Group #188948

Ben 132 reseal

July 21 2017, 12:40 AM 

I agree. Benjamin was likely referring to the fps which could be realized in the smaller caliber. But I think if 500 can be reached in .177, 400+ should be attainable in .22. I must correct an error in my prior response; I referred to another of my Benjamin pistols as a 232. It is actually a 262.

Regards,

Fred S.

 
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