Alright guys. I was able to test out the two powders which was intended to give me the lowest muzzle pressure and fastest/complete burn in the barrel.
While obviously they do give a higher peak chamber pressure, also burns out quicker and much more quiet than the factory ammo since I am treating it like an old handgun round which doesn't have to build excess pressure to cycle a bolt.
So, being a bolt action, is going to give me certain advantages than those using this as a semiauto are going to be able to get while achieving full function.
In approaching the build in this manner and not having to generate excess gas pressure for it to work, I have less to deal with and all the advantages of not having action noise (other than cycling the bolt by hand and hammer noise) and also don't have to deal with ejection port noise and pop either, so I'm approaching it from an entirely different viewpoint than I normally would and designing it as a whole for a suppressed upper.
Most of you guys have known me long enough to know that I have always been enamored with the Delisle carbine from ww2. I have came to accept the fact that I will never be able to have one, so I am building this project up as to be a more modernized and functional version of it. Sort of a purpose built "
Dee-Lyle Gen 2" so to speak which would serve the same purpose and have more energy down range to boot.
So now, I'm suddenly not as sad that I won't ever own a Delisle carbine. I just had to make a better mousetrap myself
My buddy George ran all the numbers through quickload and came up with some powders that showed a lot of promise. I went through about 3 dozen powders to narrow them down to the few that I wanted to make and try.
Initially, I had told him that I was going to use 2.250" cartridge overall length because that is what would fit into the magazine, but after I loaded a dummy round and chambered it, was FAR too long to fit into the chamber.
What occurred was extensive bullet setback to *2.213" actually* and a ring forming around the ogive and hard extraction to get it back out of the chamber. You can see the ring on the jacket in the photo below about .320" back from the tip of the bullet. Obviously, this would have been bad with a live round and would have no doubt caused an unsafe pressure spike, so this is why it is taking me much longer to develop everything. I prefer to take things slow and be cautious about it than to just go into this blindly. Or, come out blinded.
So, in realizing my mistake, I seated the bullets deeper until they had a decent amount of jump before getting into the lands and throat which chamber and extract easily by hand now, I asked him to change the numbers to show a 2.185" COL and reconfigure the numbers accordingly.
This made a much more narrow pressure window with both powders, so I'm starting low on both with a load which seems to overlap each other so I can determine which of the two powders that I like the best in terms of low sound levels and other performance before tweaking them for higher velocities and different seating depths depending on accuracy and sound and everything else.
Another thing I have done was to pick a bullet that I wanted to use for testing. There is basically no load data for these in the US. So, I'm wildcatting and barnstorming and found projo's from several manufacturers that would work, but for starters, I chose to use the Speer 270 Gr HotCor soft point bullet. Mainly because it weighs near what the factory bullet weighs, it's a soft point which may help deform a little better while deer hunting and also shorter than the factory bullet which will give me more choices for which powder I use because it doesn't take up as much room in the case.
Some modified soft points that I put on my lathe and made some deep hollow point cavities. Water bucket expansion/deformation testing coming to a theater near you soon.
I'll let you judge for yourself how it sounds.