Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Hunting
Long Range Hunting & Shooting
Muzzleloader
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="edge" data-source="post: 133879" data-attributes="member: 5030"><p>The breechplug is made from 4140 steel and is made from two pieces. The outer section that can be seen is bored for a modified 45 acp case. I bore out the primer pocket of the 45 case to accept a 209 primer, and I also run it through a 30-06 sizing die to put taper on the case. When the bolt closes it makes a tight fit on the OD of the case.</p><p></p><p>The center of the breechplug which is a shrink fit into the OD threaded section has a snout that comes within 0.005 of the headspaced acp case and has an ID that is a snug fit for the end of the 209 primer that extends inside the case.</p><p></p><p>Primary sealing is on the outside of the 209 primer similar to the Savage design and secondary sealing is on the case OD, but the cases stay clean and do not need cleaning.</p><p></p><p>The sabots are made on a CNC lathe from PVC Type II plastic. They are rifled for a snug slip fit in my barrel, but the OD has several raised ridges to grip the grooves of the bore for a tight fit. The rifling is accomplished by taking a regular Manchester style grooving tool and laying it sideways and shimming it to be on-center. The lathe is programmed for an 8 start thread with a 14 inch pitch.</p><p></p><p>Through extensive testing, I found the optimum place for the rear groove to ensure that the rigid sabot petals broke cleanly and did not interfere with the bullet/sabot separation.</p><p></p><p>While machining takes less than a minute for each sabot, sawing and deburring the saw-cut takes another 2 minutes. The boat tail makes deburring much harder and for experimenting I make sabots flat based and shoot non boat tailed bullets since they require much less time to debur.</p><p></p><p>edge.</p><p></p><p>I also shrink fit a drill bushing into the breechplug as a permanent flash hole.</p></blockquote><p></p>
[QUOTE="edge, post: 133879, member: 5030"] The breechplug is made from 4140 steel and is made from two pieces. The outer section that can be seen is bored for a modified 45 acp case. I bore out the primer pocket of the 45 case to accept a 209 primer, and I also run it through a 30-06 sizing die to put taper on the case. When the bolt closes it makes a tight fit on the OD of the case. The center of the breechplug which is a shrink fit into the OD threaded section has a snout that comes within 0.005 of the headspaced acp case and has an ID that is a snug fit for the end of the 209 primer that extends inside the case. Primary sealing is on the outside of the 209 primer similar to the Savage design and secondary sealing is on the case OD, but the cases stay clean and do not need cleaning. The sabots are made on a CNC lathe from PVC Type II plastic. They are rifled for a snug slip fit in my barrel, but the OD has several raised ridges to grip the grooves of the bore for a tight fit. The rifling is accomplished by taking a regular Manchester style grooving tool and laying it sideways and shimming it to be on-center. The lathe is programmed for an 8 start thread with a 14 inch pitch. Through extensive testing, I found the optimum place for the rear groove to ensure that the rigid sabot petals broke cleanly and did not interfere with the bullet/sabot separation. While machining takes less than a minute for each sabot, sawing and deburring the saw-cut takes another 2 minutes. The boat tail makes deburring much harder and for experimenting I make sabots flat based and shoot non boat tailed bullets since they require much less time to debur. edge. I also shrink fit a drill bushing into the breechplug as a permanent flash hole. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Hunting
Long Range Hunting & Shooting
Muzzleloader
Top