Hello,
I am new to the forum. I have had a lot of fun reading about and trying new things with "Thumper". I figured it was my time to give some info back. I have the 16" upper. I have a variety of lowers. As long as the lower is good and tight it doesn't seem to matter with the 450BM upper. Two things I would highly suggest is using a wolf extra power buffer spring and a large charging handle latch from Model 1
. I found with hunting the large mag release button was a bad idea
. My hunting lower had the Magpul CTR butstock. It is very nice and quiet. No rattle. Had my upper for about a year and have 2 deer & 3 hogs so far.
I feel that I have successfully mastered using .284 Win Brass and 230gr FMJ for plinking
. I had about 50% success from 100 of 284 win I started with but after shooting the "good" ones and reloaded them 3 times I am past the learning curve. Many have published how to make 450BM brass from .284 so I'll skip that part.
Here is what I found for a good load data. I have attached a picture taken yesterday at 100 yards. This was 10 rounds from a bench in rapid fire. Note it was a windy day 15 to 20mph so I was impressed. On a calm day it would be around 0.75-1.5” That is why I was at the rage, to windy to get lobsters on the last weekend of lobster season her in FL. I just put a new Nikon Omega Muzzleloader scope on. Mixed reviews on the scope. Optical clarity was great but when I went to 200 years you can forget their ballistic reticle….. More later about the scope.
Back to the load data. After about 3 months and 6 trips to the range here is what I found:
"450 Bobster"
Magtech Bulk Bullets 45 ACP 230gr FMJ from Cabalas P# Item :IA-215351
CCI Large Rifle Magnum Primers # 250
40.2gr Little Gun
2.225” OAL
Brass trimmed @ 1.697”
There are no signs of over pressure and they imitated the factory Hornady Load very well. I had some hotter loads but they started moving the primer out. After 60 rounds yesterday not a single primer moved with this formula. I tried some other 45 ACP bullets and they were a disaster. Must have a good copper jacket.
I found a couple of things that were critical:
If the brass is cut to short below the 1.690 and the OAL is to short then the cartridge will go too far into the chamber. The firing pin just will just barely make it to the primer and won't ignite. The cartridge also can't be removed by the bolt either. This cartridge is a dream with its straight walls but is OAL/CL still critical.
I must admit that I am trying to consolidate my reloading components. I shoot 300 win mag & 300 RUM so I have a good supply of LRM primers. In other round substituting Mag for standard was problematic but in the 450BM it was a non issue.
Here is the disclaimer: Don't try this at home, ever!
Thanks for reading,
Bob