B28 Breech Block / Barrel Re-set question

B28 Breech Block / Barrel Re-set question

Joined: May 31st, 2008, 5:09 pm

November 16th, 2011, 10:02 am #1

Last summer (2010), Walter Glover mentioned that he was getting nice velocity and firing cycle smoothness improvements by flaring the skirt of 22 cal pellets in his new B28. At the end of the thread, he mused about removing the barrel from the breech block and re-setting it (presumably removing a short section of loose breech lead-in during the process).

Anyone know if Walter did this, and how it turned out?

Thanks in advance,

Mike
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Joined: October 2nd, 2009, 10:15 pm

November 16th, 2011, 4:44 pm #2

Make it fit better,

I have the opposite information. My B28 had a breech opening that was slightly tight which did not allow the pellet to completely seat into the breech, and the skirts were getting clipped just a tiny bit. So I opened it up until the skirt was flush with the surface of the outer edge of the breech. I gained as much as 20 fps by doing this. Removing the restrictions in that port allowed the pellet to seat correctly and the skirt to properly expand and fill in the BBL. Not only did I gain power I achieved a more consistent fps average overall with a spread of only 8 fps average.
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Joined: April 27th, 2008, 3:35 am

November 20th, 2011, 4:35 pm #3

Mike , can you elaborate on the mechanics of how you accomplished this. Mine has a similar tightness
and I'd like to correct it but I don't wish to make any mistakes. A foreward Thanks Don
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Joined: October 2nd, 2009, 10:15 pm

November 21st, 2011, 4:38 pm #4

I used an abrasive rubber dremel cone tip like thishttp://www.widgetsupply.com/page/WS/PRO ... ame/D-GU01 to make the breech just big enough to fit my pellets exactly flush. If you don't have a dremel just use a drill motor. Get several so you can round one or 2 down so they don't go deep into the BBL when you polish it down. You just want to flare the first few centimeters of the port. Keep the pellet you are trying to use handy to check the fit. Once it sits flush you are finished. I kept a cleaning rod in the BBL with a mop end on it while I was polishing to push the pellet back out and keep the dust from going down the BBL.
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Joined: October 25th, 2002, 3:46 pm

November 21st, 2011, 11:00 pm #5

Last summer (2010), Walter Glover mentioned that he was getting nice velocity and firing cycle smoothness improvements by flaring the skirt of 22 cal pellets in his new B28. At the end of the thread, he mused about removing the barrel from the breech block and re-setting it (presumably removing a short section of loose breech lead-in during the process).

Anyone know if Walter did this, and how it turned out?

Thanks in advance,

Mike
Would like to give the breech leade a better prep but removing the barrel from the block would be quite a challenge. One that scares the heck out of me

The other problem would be recutting the breech seal at an angle.

So far not worth the trouble.

Walter....
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Joined: October 2nd, 2009, 10:15 pm

November 22nd, 2011, 12:27 am #6

Might be easier to purchase a Dremel with an angled head (if they make them) then just clean up the port as needed.
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Joined: October 25th, 2002, 3:46 pm

November 22nd, 2011, 4:50 am #7

pellets drop to 1/8" below the end of the barrel. I would prefer a nice push fit to seat the pellets.
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