Blank cases to 300BO?
- Thread starter Chainsaw.
- Start date
Wife and I were at the range the other day and picked up a bunch of blank 556 cases. Odd. Anything to note about blank cases? Id like to chop em off and use them for 300 bo cases.
Been using them for awhile. Treat them the same as any other 223 to 300blk conversion.
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Wreck-n-Crew
New member
Some thicker cases might give you trouble.
Here's a good read....http://www.massreloading.com/300BLK.html
Here's a good read....http://www.massreloading.com/300BLK.html
Probably more work than it's worth(250 Hornady cases are on sale at Midway for $67.99. $29.99 for 50. Sig Sauer cases are $14.99 per 50), but blanks are the same dimension as regular cases but have an integral brass "bullet". Cut that crimp off and you have a regular case. Case neck needs to be .203" long with 1.760" -.030 case length. Might not be enough brass left on the blank's neck. A lot depends on how you cut 'em. Hacksaws do not cut square.
Whisper 300
New member
Can use a cheapie Harbor Freight mini chop saw-I think I paid 20 bucks or so or use a mini tubing cutter, a bit more work but nice clean straight cuts.
If you can get the dimensions you need to form the 300 Whisper/BO case from the blanks, I see no reason not to go with it.
As always start low and watch for pressure signs- since I only shoot heavy subsonics, I have the recipes down pat and know where the low end is and work up until I achieve 1050 fps
Let us know how things work out.
Gary
If you can get the dimensions you need to form the 300 Whisper/BO case from the blanks, I see no reason not to go with it.
As always start low and watch for pressure signs- since I only shoot heavy subsonics, I have the recipes down pat and know where the low end is and work up until I achieve 1050 fps
Let us know how things work out.
Gary
Wreck-n-Crew
New member
If he needs as many cases as I do buying them new over making them is a no brainer. I picked up my brass for free and have over 1500 so far. I need a good 2,00-3,000 to even have enough to keep me loaded for a few months.
Heck it isn't hard to shoot 300 rounds a week.
Heck it isn't hard to shoot 300 rounds a week.
Whisper 300, would it be practical to make a fixture to hold the case so that you just have to slap the tubing cutter on it and it will be within a couple thousandths of the right length? That would give you the smooth square cut of the tubing cutter without the need to measure each time and be careful getting the cutter placement just right.
If you're already doing something like that then please forgive me suggesting you do what you're spread doing, but I was raised by a master machinist who did a lot of jig and fixture work, so I tend to think that way even though I am nowhere near the craftsman he is.
If you're already doing something like that then please forgive me suggesting you do what you're spread doing, but I was raised by a master machinist who did a lot of jig and fixture work, so I tend to think that way even though I am nowhere near the craftsman he is.
The mini chop saw he speaks of works great, add a jig from Squirrel Daddy and you can cut alot of brass pretty quick.
Id think a tubing cutter would one, squeeze the case to much before it cut it off and two, being the case is tappered would roll pff the end lest you have a jig that could some how prevent that.
Id think a tubing cutter would one, squeeze the case to much before it cut it off and two, being the case is tappered would roll pff the end lest you have a jig that could some how prevent that.
Whisper 300
New member
Re: tubing cutter----I guess a fixture could work but the small size of the 223 and the relative large size of the cutter-even a mini - sort of makes me think it would be more trouble than it is worth.
When I do use a mini-tubing cutter, which is not often anymore, I simply cut beneath the neck and then trim it down to size using WFT trimmer - easy,peasy.
Like Chainsaw wrote the HF mini chop saw is the cheap and easy answer-it even comes with a built in jig of sorts - just set the limiter to what you need and cut away.
Gary
When I do use a mini-tubing cutter, which is not often anymore, I simply cut beneath the neck and then trim it down to size using WFT trimmer - easy,peasy.
Like Chainsaw wrote the HF mini chop saw is the cheap and easy answer-it even comes with a built in jig of sorts - just set the limiter to what you need and cut away.
Gary
Rottweiler
New member
Do those blank cases have a ring/groove down near the base like old .30-06 blanks? that makes a weak point for case separation when fired. I had that happen once
I know one company that has converted pallets of 233 blanks over to 300 blk.
They use the 3rd generation of this machine I built.
https://www.youtube.com/watch?v=iNXz97yWp2w
They use the 3rd generation of this machine I built.
https://www.youtube.com/watch?v=iNXz97yWp2w
Blank cases are traditionally made with defective brass that fails testing off center flash holes will get an entire production lot scrubbed, as will alloy that come up weak, poor drawing, etc, you may wind up with brass that didn't meet production standards and may be unsafe to fire. You may find brass that was dumped from production because too many were tested that failed in a lot, but we're otherwise good. You might even find brass that was perfectly fine that was diverted to blank production because it was needed.
This isn't just an urban legend, I've dissected some blank cases and found these problems.
Do what you choose to do, but myself, NOT EVEN ON A DOUBLE DOG DARE.
This isn't just an urban legend, I've dissected some blank cases and found these problems.
Do what you choose to do, but myself, NOT EVEN ON A DOUBLE DOG DARE.