M Neck Expander / Powder Dies

M Neck Expander / Powder Die
Now, M-Dies for Dillon Square Deal B, 550, 650 and 1050 progressive presses!
If you have discovered the advantages of M-Die expanding and own a Dillon Square Deal B, 550, 650 or 1050 progressive press, then you know the frustration of having to interrupt the process to M-Die the cases before powdering. Now you can replace the Dillon expander/powder die with these M-Expander / Powder dies.
They will actually speed up the process by not having to "balance" the bullet on the case mouth trying to get it perfectly vertical to seat.
The M-Expander / Powder die allows the bullet to enter straight down approximately 1/10" into the case perfectly concentric, then seated to depth as normal.
Made in the USA, from quality steel to exacting tolerances.
19+ handgun cartridges as listed below.
Inquires and orders online only. Positively will not take questions / orders by phone!
Purchase by PayPal preferred.
Prompt delivery via USPS Priority Mail.
$68.00 each, plus $9.20 shipping whether you order single or multiple dies. USA orders only.
Email orders only to: Lou@LousGunWork.com
Email your order with the cartridge(s) and quantities wanted along with your name, shipping address and phone number.
You will be sent an email with a payment request via PayPal.
You can then review the total before finalizing payment, and we will ship promptly.
If you cannot use the above prescribed payment method, please state in your email order and we will try to accommodate.
Please Note: Not Recommended For Use With Polymer Coated Bullets
Cartridges Bullet Sizes Step 1 Step 2 Part Number In Stock
380 Auto, 9x19 Parabellum .354 - .356 .353 .357 100341 Yes - Ready to Ship
38 Super, 9x23 , 9x25 (NOT for 9x19mm or 380) .354 - .356 .353 .357 100361 Yes - Ready to Ship
38 Special, 357 Mag, 357 Rem Max, 38 S&W .357 - .359 .356 .360 100381 Yes - Ready to Ship
40 S&W, 10mm Auto .399 - .401 .398 .402 100401 Yes - Ready to Ship
44 Special, 44 Mag, 44 Russian, 445 Super Mag .428 - .430 .427 .431 100441 Yes - Ready to Ship
45 ACP, 45 Win Mag, 45 Colt, 454 Casull, 45 Schofield .451 - .453 .450 .454 100451 Yes - Ready to Ship
Click For A Larger Image - Image Indicates Step 1 and Step 2 Portion Of The Die  
The Advantages of M Dies  
Conventional expanding dies expand cases approximately .001" - .003" under bullet size and flare the case mouth to allow the bullet to be set on top of the mouth. If the bullet is not set on perfectly vertical, and concentric to the case, it will enter askew. Upon firing the bullet enters the chamber throat and/or forcing cone of the barrel in that skewed manner, deforming the bullet and affecting accuracy.  
With a single stage press this accuracy problem can be dealt with by using an inline or seating alignment die. Or, thanks to innovative thinking, M Dies are now available.  
The Dillon machines however have their expanding dies integral with the powder dies. Therefore, the dies offered here are made to facilitate the Dillon progressive presses to take advantage of the increased accuracy obtained by M Dieing, but also eliminates the little extra time it takes to "attempt" to get the bullet as vertical as possible and perhaps pinching fingers in the process.  

Symptoms caused by non concentric bullet seating  
Bulging Cases:
If you turn a conventionally hand loaded cartridge in your hand, focusing your eye where the base of the bullet rests in the case, you will probably notice an non concentric somewhere along that 360 degree line. This is caused by the bullet sitting askew in the case. This bulged case condition not only effects accuracy, but more importantly chambering.
Bulged cases are especially detrimental in semi-auto pistols with match grade barrels or tight chambers. These bulged cases will actually prevent the round from chambering at all. Factory rounds are seated perfectly concentric and do not hinder chambering. You can duplicate that advantage by eliminating bulged cases in the reloading process.  
Note: As with all M-Dies, you may want to use a Lee Factory Crimp die for final post-sizing.