Mountain Mould - 405 Winchester

[Gemsbok405]

100201Had a custom mould designed on Mountain Moulds web program for my Winchester / Miroku 1885 in 405 Win. This a "Traditional Hunter" model with 28" barrel and metal crescent butt plate.

Target was to achieve .40-72 loading upwards, call it .40-72 +P, but below full 405 Win power... 1800 - 1900 fps.

Design was Bore Riding Tangential Ogive with bore ride, no crimp. Design weight was 330gr GC-WW. Nose at 50% (nose with front band) of LOA 1.000. With gas check fitted was 1.026" Bore ride at 0.050" ahead of front band.

Final cast product (approx Lyman #2) was 325.7 gr with lube and gascheck, but was a brilliant fit with SAAMI 405 Win chamber / throat. The bullet is a press fit into muzzle, nominal bore ride at 0.405"/cast 0.4055" and shows potential of good accuracy.

When fit cartridge into rifle, bullet has a soft / firm fit, with no engraving of lands into B/Ride, but if use a thin black marker on BR, the lands cut the market paint at 0.327 from bullet nose. With leade starting at about 0.362, and front band at 0.382, front band has 0.020" clearance when fired.

Have loaded some rounds, and will test in 2 weeks time!

[Elkins45]

I have a couple of Dan's molds and the quality is first rate. One thing about Mountain Molds: if the boolet doesn't shoot well unfortunately you always know who to blame.

[Andrew Mason]

gemsbok405...

how much of the bullet protrudes out of the case?
what is your COL?

[.22-10-45]

Curious as to what your groove dia. is?

[Gemsbok405]

Andrew

the Hornardy .405 case ( factory - untrimmed) is 2.570"

Bullet nose (incl. front band) is 0.502

Seated 0.006 into front band to close off front lube groove

= 2.570 + 0.502 -0.006 = 3.066: COL

[Gemsbok405]

.22-10-45

Have a Ruger 1-H in .405, most measures on web talk about 0.412

My 1885 Win / Miroku .405 Win is from first batch *****MX85, measures listed have been around the 0.4115 #

Will get to measure both some time in future...

[Gemsbok405]

Tested the cartridge yesterday. Loaded with 55.0 gr Somchem S365 (similar H-4350) and 1900 fps and 2 MOA... shot freestyle off bench.

Clocked at 1912 fps average 3 shots...shoulder clocked out after 10 shots from crescent butt plate!

With bags could easy get to 1 MOA, but 58 year eyes and round bead front post ( 1885 Win-roko), sight picture is limiting factor.

Will be testing in a Ruger #1-H with scope in a month of so...

[Nrut]

Put a thick butt pad on that Ruger and it will be a pleasure to shoot off the bench..