Steel breech Rear Screw Size

[Nightsniper52]

I had bought a Steel Breech 2240SBPK and it didn't come with the shorter rear screw like in the Kit you buy.  Does anyone know the Length and Thread Size???  And the size of the set screw for the Barrel??  I thought about getting both in a Allen head.    Thanks Jeff   

[JEBert]

Screw for rear of Crosman Steel breech is an 8-32 X 0.685 ~ .003 (11/16") and button head Allen screw is warranted if wishing it to not protrude above the upper breech surface.  I got the above length for my gun by taking the rear plug out of the gun, then screwing the screw into the rear plug until it just reaches the inside of the plug.  Not so far as to interfere with the hammer spring.  Then count the exact number of turns it takes to unscrew it until it clicks indicating that it is all of the way out.  With everything installed except the screw, put the screw in place, turn it counter-clockwise until it clicks, and then turn it back in that same number of turns.  Now, turn it in until it is tight continuing to count the turns. That last number of turns is how many threads you need to grind off of an 8-32X3/4 button head Allen screw.  It should be about two threads (at 32 threads per inch, two threads would equal 1/16").  I got my Allen screws at Lowe's or Home Depot in stainless steel.  It might have been OK if I had left it at 3/4" but I wanted to be sure that it didn't interfere with the hammer spring.
The setscrew hole for the barrel is tapped for an 8-32 setscrew.  If you want to order them from Crosman: part# 88-089 @ $1.15 each.
Cheers,

[BDS]

Screw for rear of Crosman Steel breech is an 8-32 X 0.685 ~ .003 (11/16") and button head Allen screw is warranted if wishing it to not protrude above the upper breech surface.  I got the above length for my gun by taking the rear plug out of the gun, then screwing the screw into the rear plug until it just reaches the inside of the plug.  Not so far as to interfere with the hammer spring.  Then count the exact number of turns it takes to unscrew it until it clicks indicating that it is all of the way out.  With everything installed except the screw, put the screw in place, turn it counter-clockwise until it clicks, and then turn it back in that same number of turns.  Now, turn it in until it is tight continuing to count the turns. That last number of turns is how many threads you need to grind off of an 8-32X3/4 button head Allen screw.  It should be about two threads (at 32 threads per inch, two threads would equal 1/16").  I got my Allen screws at Lowe's or Home Depot in stainless steel.  It might have been OK if I had left it at 3/4" but I wanted to be sure that it didn't interfere with the hammer spring.
The setscrew hole for the barrel is tapped for an 8-32 setscrew.  If you want to order them from Crosman: part# 88-089 @ $1.15 each.
Cheers,

+1 to JEBert's comments, and the critical features are length and the lo-head of the screw so as not to interfere with mounting of scope rings or other stuff.

[Nightsniper52]

Thank you so much!!  Im off to the hardware store.   

[1377x]

could you shorten the stock screw you have?

[Nightsniper52]

I could with no problem.  But I would like to change it to Allen head.  Thanks Jeff

[BDS]

I could with no problem.  But I would like to change it to Allen head.  Thanks Jeff

Button Head, Button Head, the typical socket head capscrew ("Allen head") will protrude quite a bit past the dovetail.

[1377x]

Button Head, Button Head, the typical socket head capscrew ("Allen head") will protrude quite a bit past the dovetail.

its the round head with allen keyhole, right?

[BDS]

Yup, it's this guy 

OK, it's a big picture of a little screw! 

PS Button-heads work great at the upper/rear frame screw too, you know, the one that digs into the web of your hand 

[1377x]

thats what i thought you talking about!

[crossliner]

Screw for rear of Crosman Steel breech is an 8-32 X 0.685 ~ .003 (11/16") and button head Allen screw is warranted if wishing it to not protrude above the upper breech surface.  I got the above length for my gun by taking the rear plug out of the gun, then screwing the screw into the rear plug until it just reaches the inside of the plug.  Not so far as to interfere with the hammer spring.  Then count the exact number of turns it takes to unscrew it until it clicks indicating that it is all of the way out.  With everything installed except the screw, put the screw in place, turn it counter-clockwise until it clicks, and then turn it back in that same number of turns.  Now, turn it in until it is tight continuing to count the turns. That last number of turns is how many threads you need to grind off of an 8-32X3/4 button head Allen screw.  It should be about two threads (at 32 threads per inch, two threads would equal 1/16").  I got my Allen screws at Lowe's or Home Depot in stainless steel.  It might have been OK if I had left it at 3/4" but I wanted to be sure that it didn't interfere with the hammer spring.
The setscrew hole for the barrel is tapped for an 8-32 setscrew.  If you want to order them from Crosman: part# 88-089 @ $1.15 each.
Cheers,

Mr. Jebert what is the drill bit size again for that 8-32 set screw? I intend to fortify my barrel and install 2 more set screws. Must be here somewhere but it seems the info is playing hide and seek w/ me  Thanks and best regards.

[JEBert]

what is the drill bit size again for that 8-32 set screw?

I don't remember what size comes with the tap if you purchase them as a set but I have a chart that calls for a #27 for 50% threads in iron and stainless steel or #29 for75% threads in aluminum and plastics.
You could get away with 9/64" for either material if you are careful.
Cheers,

[crossliner]

Thank you 

[cmj21973]

Irwin/Hanson #80187, 13 piece all purpose drill and tap set.

8-32NC tap/ #29 drill

Drill and tap chart:
http://www.bing.com/images/search?q=drill+and+tap+chart&view=detail&id=FEB76D1E61C3290469B55597C5B5C62AFEF96063&first=1

P.S. Use cutting oil/light machine oil when cutting threads and take your time.

[crossliner]

Thank you sir