A tip for installing a seal

[ezman604]

I bought my Benji Super Streak back in October 09. I ordered a new piston with seal, mainspring and breach seal since I planned on doing an immediate home lube/tune. After breaking it down, I discovered the seal was torn pretty badly in a couple of places. So I was proud I had pre-ordered the replacement parts. I lubed and installed the new seal/piston. The end cap on the Benji chamber is threaded. A good safety device to make sure everything stays where it's needed but a real PAINwhen you install a new seal. As I worked the new seal/piston in place, I quickly discovered how the factory seal got buggered up. The threads on the end chewed a little on my new seal. DARN....I went ahead and finished assembling.

I found out the Walther Falcon Maccari seal worked great for the Benji so I ordered a couple. After they arrived, I used one in my Powerline 1000S and proceeded to tear the Benji down to install the great new seal. When I got ready to install, I lightly lubed the rim of the seal with moly. Trying to be very careful asI worked it into the chamber andpast the threads. I heard that terrifying tearing sound and saw a little sliver of red seal hanging just past the threads. DARN!!!!!!

Well, I ordered some more Maccari seals.Now I'mREALLY determined to get a clean install. After pondering the installation, I devised a plan. Below you will see the pictures of my install that went PERFECT. I now have an excellent, better than factory, piston seal and can't wait to chrony it tomorrow. There's probablyother airguns out there that use a threaded end cap. This little trick will work for any of those and probably save you money and seals. Just hate that it took me 3 seals to finally learn a lesson. Hope this is useful to at least one person.

Happy Shooting....and modding!!!!

Dave

[Gene_SC]

Hope that was an old seal Dave...

[snookman]

What do you see wrong Gene. I am interested in doing home lubes and maintenance so I read everything I can about it. the sleeve looks like a great solution for getting by the threads. snookman

[Gene_SC]

Nothing wrong just the seal is no good...:) Looks like he found a cure.

[ezman604]

HeeHee...yep Gene, that picture was of mythird torn seal. The original factory seal was torn worse than that. The second factory seal I installed tore some and this Maccari caught on the threads too. Just hate that it took me 3 seals to figure it out. Got a fresh and complete seal in there now. Will chrony it later today.

[Bogey]

Good idea.   Thanks for sharing this tip with all of us.

[ezman604]

You're quite welcome Mike. Hope it helps at least one member here!!!!

Well, I've been struggling with my Benji conversion from .177 to .22 for a while. Very frustrating at times, just finding all the parts for one thing. After waiting 2 months for the new barrel,it was shooting like a shotgun as far as elevation. Windage was fine, just all over the place with elevation. Had great lockup too, so that wasn't the issue. After tearing the gun back down and looking at my seal, I thought this HAD to be the answer. Last night, as pictured above, I replaced the seal one more time with a Maccari Walther Talon/Hunter seal. Sorry, I stated earlier it was a Falcon seal. Anyway, I just took it outside and ran a few rounds through the chrony. With CPHP 14.3gr, I'm getting an average of 800fps and out of 20 shots had a spread of 14fps. Some rounds were looser in the breach than others. That gives it an output of over 20fpe. I'm very pleased with the power and it may increase as I put a few hundred more rounds through it andall internalsget settled in.

Now the best part. I set my target stop out at my usual 25 yards. Remounted the scope and took 2-3 shots to get it dialed in. Then concentrated on my 8" round Shoot-N-C target. You can check out the results below. I'm THRILLED to say the least. A smalldefect in a seal will make a HUGE difference in accuracy, I'm hear to tell ya.

And I've heard you guys talk about stacking pellets and punching the same hole but it's not the same as doing it yourself. HeeHee

HAPPY Shooting....and modding!!!!

Dave

[Bogey]

There ain't nothing like that feeling you have  when you get it right.     Grouping looks very good especially for 25 yards.

[snookman]

Good to see you got her dialed in. There is nothing better to a shooter than a rifle that shoots good groups. I don't care how beautiful a gun is, if it's not accurate, it's not worth having. snookman

[Ray]

Great tip. You wernt worry about the sharp edge of the can cutting the seal?

Ray

[ezman604]

Thanks Ray, and it nevercome in contact withan edge.

[shadow]

Now that's thinking outside the box and inside the tube, great idea bro.:) Ed