milled and finished uppers work on the AR15 platform for big bores like
the .458 Socom, .450 Bushmaster, and the 12.7x42(.50 Cal). We took ours a few steps
further and opened our ejection port opening to 0.64in instead of the
standard 0.62in and we also opened the upper right side for no cycling
issues spitting out the big bore brass. For the finishing touches to
make this a true big bore upper we blend the feed ramp to aid in the
center feed design unlike most that still have the M4 .223/5.56 feed
ramps, which is not needed in the .458 design. We then sand all
openings and edges to remove any burrs to aid in the ejection of the
brass. At that point we still weren't happy enough so we went one step further, we do an additional undercut to the inner upper portion of the ejection Port opening to aid in the brass ejection. So there are absolutely no hang ups, taking these a step above the rest. We then sand all openings and edges to remove any burrs to aid in the ejection of the brass.
Upper will come as stripped upper only, unless hardware kit
option is selected. Hardware kit includes, ejection port door, rod,
spring, c clip, forward assist button, spring, and pin. Please add in
notes if your prefer hardware package loose or installed by us.
• Larger ejection port opening
• Blended center feed ramp
• Hand smoothed and inspected
• All casting ugly casting marks are sanded smooth
• 7075 Aluminum
• T6 Heat Treated
• 80% Machined Lower (just needs trigger and safety well machined)
•Magwells are flared and broached for ease of magazine swaps
• Optional CA Compliant Engraving
Our 80% lowers are of the same high quality materials as are uppers.
80% lowers is NOT an FFL item. No FFL is required for transfer and
machining, please machine work MUST be done solely by the buyer to keep
the ATF from knocking at your door. The only things left to finish this
off into a fully functional lower receiver is to mill the trigger
pocket, safety selector, trigger and hammer pins. The rear lug pocket is
already complete, one less step to worry about.
our other products if you're interested in other calibers such as
improved .300 Blackout uppers, .223/5.56 improved uppers, 6.5 Grendel,
also complete uppers (barrels, hand-guards, muzzle break, charging
handle, bcg). Feel free to email us with any questions.
*No returns accepted, all sales are final*