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jmorris
01-11-2014, 06:38 PM
The first gun given to me was a Benjamin .22 cal air rifle when I was 11 but it has been dead for years due to worn out parts. After ordering an RWS 34 to play with I came across a rebuild kit from Pyramyd air that cost about $28 including the special tool to take them apart (I was quoted $100 to rebuild it years ago).

Start by removing the stock screw and stock. Then remove the two roll pins that hold the muzzle cap inplace and bring the piston/rod back far enough to line up the pump handle pin with the lower muzzle cap hole and remove that pin. Now you can replace the piston head.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140148_195_zpsbcb63fb3.jpg

Next remove the trigger/safety (don't loose the detent ball for the safety) and rear retaining cap. The spring and hammer are under a little pressure but not too much, in any case remove these parts.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_140413_347_zpse37f43b2.jpg

They send a tool that is square on one end that allows you to remove the retainer for the valve body.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141341_021_zpsefa43a2c.jpg

Opposite the square end of the tool, it is threaded to remove the valve guide. This took some "tapping" to get this out of mine.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_141407_713_zpsc2568a57.jpg

The kit comes with all of the seals you need to replace and a new check valve spring but I did reuse the original lead washer instead of the PTFE split washer they provided.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_142635_196_zps7932f7a6.jpg

Be VERY careful reassembling the valve body retainer. If you mess up the threads, both are brass and fine thread, you are going to be SOL. I put the tool in a vise and rotated the tube around while keeping everything in alignment. This too will take a little pressure (I also used air tool oil).

Then reassemble the rest like it came apart. I also cleaned everything once I had it all apart.

Before it wouldn't hold enough air to move a pellet and I have no idea what they are supposed to be but with a 14.3g pellet

3 pumps avg 407 fps
5 pumps avg 507 fps
10 pumps avg 647 fps

5 pumps and let it sit for half an hour went 505.6 with a second 5 pump shot right after going 505.0, so I guess old faithful is back in business.

http://i121.photobucket.com/albums/o213/jmorrismetal/reloading/air/IMG_20140111_155444_277_zpsebb4fa6f.jpg

digger44
01-11-2014, 07:28 PM
nice write up

WRideout
01-13-2014, 07:23 AM
I have a great affection for those old air rifles. I remember other kids telling outrageous stories about the destructive power of ten pumps in one of these. When I lived in TN, I saw a kid hunting squirrels with a pump air rifle; its legal down there.

Wayne

GT27
01-13-2014, 01:33 PM
Thanks for info,I can suggest the Williams peep sight for the Benji,made mine into a real tack driver!

tnpaw
01-19-2014, 11:03 PM
Times two on the Williams Peep! Just put one one my Benj .177 and .22 this past summer! Made all the difference in the world!

jmorris
01-21-2014, 09:21 AM
How does the Williams sight mount?

grizzlyadams
01-21-2014, 12:01 PM
on the newer guns, there are holes pre drilled and tapped on the side of the receiver for it. you gun looks like a model 342? it may no have the pre drilled holes

jmorris
04-05-2014, 04:52 PM
It is now kid approved.

http://i664.photobucket.com/albums/vv5/qvideo/IMG_20140329_145554_298_zps60605f82.jpg

JesterGrin_1
04-23-2014, 04:06 PM
I would like to ask a couple of maybe dumb questions. Where did you get the scope mount? And will a Benjamin like yours but in .177 put down a Raccoon?

Gunor
04-23-2014, 04:28 PM
Jestergrin,

I went thru the scope mount issue with my Benjamin 397 - made in 1994 - bought what I thought would fit. Benjamin B272 - did not fit my receiver diameter - only for current production models.

I read that the B270 would fit - but haven't seen any of those...

http://www.network54.com/Forum/275684/thread/1165720714/Can+anyone+describe+what+the+Sheridan++scope+inter mounts+look+like

See if that thread works for a little more info.

Geoff in oregon

digger44
04-23-2014, 05:03 PM
Jester a 22 benjamin is a better choice for something the size of a coon, but yet a 177 will do it. I've had model 342, 310, 347, and now a 317 and they've all taken coons, possums, barn cats etc. the 22 has a little better killing power. Your best bet with the 177 is a HEAVY pellet.

JesterGrin_1
04-24-2014, 03:42 AM
My old Benjamin is probably a little older lol. I got it Brand New in 72 I think. Could have been 71 and I think it was $30.00 out the door at the time. I wanted the Sheridan Blue Streak but it was like $10.00 or so more and at 9 or 10 years old I just could not swing it lol. :)

Sorry I have never looked at the weight of pellets. When I go back to Wally World I will take a look to see what they have as far as weight.

But I am glad I found this thread as you might have noticed my Old Benjamin has a few years on it and I think it is in need of a rebuild as it will do something odd. If I pump it say 7 or 8 times and fire it there is still pressure in the rifle. Or to say it does not release all of the pressure with the shot?

jmorris
04-25-2014, 09:45 AM
The original scope mounts I had for the rifle when I was a kid were machined from brass square bar stock and a perfect fit. The ones that are on the rifle now came from eBay