Bogus Ben 132 Reseal Experience

Bogus Ben 132 Reseal Experience

Joined: March 18th, 2006, 5:31 am

July 20th, 2017, 2:57 am #1

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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Joined: May 31st, 2005, 5:24 am

July 20th, 2017, 6:13 am #2

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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Joined: July 22nd, 2011, 4:46 am

July 20th, 2017, 12:43 pm #3

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.
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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Joined: March 18th, 2006, 5:31 am

July 20th, 2017, 3:39 pm #4

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.
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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Joined: March 18th, 2006, 5:31 am

July 20th, 2017, 3:45 pm #5

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.
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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Joined: August 14th, 2011, 5:09 am

July 20th, 2017, 4:10 pm #6

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.
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.
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Joined: May 20th, 2005, 1:44 am

July 20th, 2017, 10:15 pm #7

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.
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.
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Joined: March 18th, 2006, 5:31 am

July 20th, 2017, 11:07 pm #8

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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Joined: May 20th, 2005, 1:44 am

July 21st, 2017, 12:19 am #9

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.
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Joined: March 18th, 2006, 5:31 am

July 21st, 2017, 4:26 am #10

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.
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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