MBC Plunk Test Failure

[Rule3]

Also if you look at the bullets you bought from MBC on their web site you will see they recommend that you seat that bullet to approximately 1.08 OAL. You are good to go.

In my CZ Custom (very short leade) the bullets need to be seated very short. They just plunk at 1.06.

The small ball profile is kinda round and fat. Regular more pointed shaped 9mm are no problem.

http://missouribullet.com/details.php?prodId=51&category=5&secondary=8&keywords=

#356125M
.356 Diameter
9mm Parabellum
124 Grain 9MM RN
Brinell 18
For General Shooting
NOTE: Seat to approximately 1.08"
Price per box of 500

 

[LiveLife]

MBC 9mm 124gr "small ball" with Hi-tek ... OAL of 1.15. When I do this the plunk test fails and sticks in the barrel (Glock 43 and a Sig P320 compact)

... I'm guessing this is due to the shape of the MBC ... tested in my Sig at 1.10 and worked just fine. Pulled the Glock out of the safe and it did not pass. Now it's time to set at 1.08 and test again

Yes, MBC 9mm 124 gr RN "SmallBall" loaded to 1.150" OAL sticking in the barrel is due to the nose profile (ogive) of the bullet. If you look at the comparison illustration below, instead of more typical longer pointed nose, SmallBall has shorter rounder nose that increases the bullet base/bearing surface length that engages the rifling.

Comparison picture below shows MBC 124 gr RN (SmallBall) with longer bullet base/bearing surface than more typical Dardas/ZCast RN (stepped) that have shorter bullet base. Benefits of longer bullet base are deeper seated bullet base which increases neck tension and more consistent chamber pressures (compare bullet bases of SWC/CN bullets to bullet bases of two stepped RN bullets).

As you found out, MBC SmallBall needs to be loaded shorter to clear the start of rifling in most barrels and I use 1.080" OAL for my barrels.

 

[SARuger]

I had to load the small ball to 1.05" to pass the plunk test in my lone wolf barrels. Starting load of be-86 was a good combo

I use 5.8g of HS-6 and it's really accurate, better than I can shoot them.

 

[Jesse Heywood]

If the case bulge is where the bullet is situated, it is most likely caused by the bullet diameter. Cast lead bullets are usually .356-.357 diameter. Jacketed are .355. Most all dies are made for jacketed bullets, so when a lead bullet is seated the brass expands where the bullet is seated. You can live with the issue (most do) or invest in a set of RCBS Cowboy dies, which are designed for the lead bullets.

 

[1KPerDay]

Just wanted to say good job to the OP since he seems to be starting out right.

 

[Kaldor]

Also if you look at the bullets you bought from MBC on their web site you will see they recommend that you seat that bullet to approximately 1.08 OAL. You are good to go.

Yup, I used to seat those at 1.10" for my S&W. They are lil fattys, thats why I call them Fat Ball

 

[Tcruse]

I see you did not mention the pistol you are loading for, but I will add this.... Not every bullet offered for sale can be successfully reloaded for every pistol sold. This statement is true of combinations including the MBC 124gr Small Ball and pistols for Eastern Europe, such as the CZ series and the Springfield XD series.

Hope this helps.

I recently started using a 1911 9mm with a match barrel. All of a sudden my reloads would not fully seat and would "stick" in the barrel causing major problems. The same reloads work find in my Glocks and IWI Baby eagle. When your used brass was shot by a gun with a loose chamber, the bottom few thousands of an inch get expanded (e.g. Glock Smile) and if you follow the standard "rule of thumb" for the sizing die (adjust until touching shell holder and back off a turn) the case is not fully sized. Using Lee dies, I was able to solve most of the problem by thinning the top portion of the shell holder and adjustment of the sizing die to "hard" touch the shell holder. After this approach, I found the U-Die (a Lee die that is made a thousandth smaller) as an easier solution that does not require "grinding" on the shell holder. However, you still need to have the sizing die touch the shell holder. In the beginning do the plunk test with all of your reloads until you are 100% sure that they ALL pass. Also, do not over crimp the tension to stop bullet set back is the result of the sizer not the crimp for 9mm.

My preference in 9mm bullets is Precision Delta, Acme coated, Frontier and X-treme in 124 grain. Acme can become smoky using very hot burning (high nitro) powers like Tite Group. However, Tite Group does give good accurate loads with Acme coated bullets.
My go to powders for 9mm is CFE-P, HP38/W321, and Tite Group. If when purchasing powder all three are priced the same, I usually go with CFE-P as being the most versatile and cleanest for the calibers that I reload for. For seating depth, I usually copy commercial ammo for the bullet shape. Note, Good-To-Go uses Acme Coated bullets so they are the source for my seating depth for that shape.