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Author
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Topic: Not really a coyote rifle but having some problems.
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92soggy
Knows what it's all about
Member # 4362
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posted February 05, 2016 05:39 PM
I just got a new to me 6 Dasher, supposedly had 30-40 rounds through it.
40xbr
28 in Krieger 8 twist .2704 neck.
.050 firing pin protrusion.
First fire forming load with the false shoulder method was 30 grains of varget with a 105 Jlk. Primer cratered badly and ejector mark was clearly visible. Blow length is 1.53-1.534.
Since then I've tried down to 26 gr varget and 25 gr Re-15 and all have cratered primers and ejector marks. Sticky bolt lift occurs at 31.3 grains varget
Next I tried some formed brass with 30 gr varget, 105 Jlk and 3 different primers: cci 400, 450 and rem 7.5.
I tried turning the necks on a couple down to about 4 thou clearance( non turned is about 1.5 thou clearance)
Cast the chamber. Everything looked good there.
Swapped firing pins, which helped on the cratering.
Tried some 107 Smk.
Played with seating depth quite a bit.
Removed the ejector.
Scrubbed the throat with JB, thoroughly cleaned the rest of the barrel.
I think that's about all I've tried, every load whether fire forming or formed already is showing signs of pressure.
What are your opinions?
Posts: 39 | From: Washington | Registered: Mar 2013
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Leonard
HMFIC
Member # 2
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posted February 05, 2016 07:35 PM
The first thing I would do and it's not clear to me that this is what you are doing; work up your load from every source possible. I don't have any data on a 6 Dasher so I don't know if 30 gr. of Varget and a 105 jlk is a light load or midrange, or whatever? The primer is the last thing I would switch? But, if I had cratered primers @26 gr. of Varget or the R15. I certainly think it's time to stop and reevaluate things without going to 31.3 gr of Varget. Sorry if I'm not understanding you?
The chamber neck diameter is .2704 but what is the wall thickness? What do you mean "4 thou clearance?" Is that on the over all length?
There must be truth somewhere but I have not looked up data, so you could be either way off or exactly within parameters? I think I would talk to the guy you bought it from. If he is helpful that's one thing but if he is defensive, you might have taken a real problem off of his hands?
Good hunting. El Bee
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EL BEE Knows It All and Done It All.
Don't piss me off!
Posts: 31465 | From: Upland, CA | Registered: Jan 2003
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92soggy
Knows what it's all about
Member # 4362
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posted February 05, 2016 09:43 PM
Yes I did my best to gather all info for loading for this cartridge, in this case that was limited to a couple of forums and quickload.
30 grains is a light to mid range load, with most guys running in the 32.5 range.
Un-turned loaded round measures .269 giving 1.5 thousandths total neck clearance, I did turn 2 cases down so that the loaded round measured .2665 giving 4 thousandths clearance. I don't have any way to measure the actual wall thickness.
I am starting to think I may have solved someone's problem for them but I want to make sure I'm not overlooking something before I take any further steps.
Thanks, Chad.
Posts: 39 | From: Washington | Registered: Mar 2013
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DAA
Utah/Promoted WESTERN REGIONAL Hunt Director
Member # 11
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posted February 06, 2016 05:23 AM
Are the primers still radiused at the corners? Not flat?
If so, I'd guess the cratering isn't a pressure sign. Just a sign to turn and bush the tip.
Still getting ejector hole marks with the ejector removed? How is the edge of the hole?
Just to make sure I'm following - same, same is happening with fireformed cases, right? Would not think headspace if so. But still curious how it feels if you remove the firing pin and close the bolt on an un-fireformed case. Have some crush? It should.
- DAA
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"Oh yeah, they're gonna talk to you, and talk to you, and talk to you about individual freedom, but they see a free individual, it's gonna scare 'em." -- George Hanson, Easy Rider, 1969.
Rocky Mountain Varmint Hunter
Posts: 2676 | From: Salt Lake City, UT | Registered: Jan 2003
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DAA
Utah/Promoted WESTERN REGIONAL Hunt Director
Member # 11
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posted February 06, 2016 05:37 AM
Just thinking out loud...
Stiff bolt lift comes late with the Dasher. Pretty minimal taper. By the time you get there, you're well into high pressure land.
But... You don't see it for like, 5 grains over where you're seeing the primer and ejector stuff.
My pure guess, is those cratered primers and ejector marks are lying. They're trying to tell you something, but high pressure isn't it.
Or, not! That's about as pure a WAG as could be. Could easily be dead ass wrong.
Don't "think" you have headspace going on, but would like to see it clearly ruled out. My Dasher is a .20, easier to form, no necking up then back down. Just kept running the die down until I was able to close the bolt (with firing pin removed) on an empty case with good feel. Snug, but not so tight as to gall a lug or anything.
That was one I fireformed for without bullets in the garage using pistol powder. Just so much capacity difference, before and after, and likely a short life to boot.
- DAA
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"Oh yeah, they're gonna talk to you, and talk to you, and talk to you about individual freedom, but they see a free individual, it's gonna scare 'em." -- George Hanson, Easy Rider, 1969.
Rocky Mountain Varmint Hunter
Posts: 2676 | From: Salt Lake City, UT | Registered: Jan 2003
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92soggy
Knows what it's all about
Member # 4362
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posted February 06, 2016 07:55 AM
The primers are still radiused.
The first 20 shots or so as I kept working my way down the charge range they were cratering really bad and even pierced a couple. I took the firing pin out and it was flat across the tip, like someone had filed it down to get less protrusion, that didn't look to good to me so I swapped it out with another one I had. Now the primers are not so bad, I'm betting you're right about it needing a bush job.
Still getting marks with the ejector gone, the hole does appear to have a little ridge around it in some spots, hard to say really but it does seem to catch right at the edge if you run a screwdriver along it.
Yes the same is happening with formed cases. The bushing die I was using to neck them down and set the false shoulder didn't go down far enough to give any loose headspace. When you close the bolt on it its very hard to close and the shoulder is visibly moved back. Basically I'm setting the headspace when I chamber them if that makes sense?
I just went and measured the headspace with a .375 comparator, they were 1.236-1.238. One that had been fired multiple times was 1.240. With a piece of tape on the bolt nose and the firing pin and ejector removed the 1.240 case would not close, the 1.238 case required heavy pressure to close, and the 1.236 required moderate pressure to close the bolt on.
Now that you mention I shouldn't be close to hard bolt lift, the ones that were harder to open the bolt on were the ones that measured 1.240. I tried chambering them again and they definitely took a some pressure to close the bolt on so I'm guessing they are just at the point that they need resized. They have been fired probly 5-6 times.
Anyways thanks for the help and I hope all that made sense.
Posts: 39 | From: Washington | Registered: Mar 2013
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DAA
Utah/Promoted WESTERN REGIONAL Hunt Director
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posted February 06, 2016 02:32 PM
I think I'd just dress up the ejector hole and ignore the primer craters for now. Just watch the corner radius for flattening.
Really doesn't sound like pressure.
- DAA
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"Oh yeah, they're gonna talk to you, and talk to you, and talk to you about individual freedom, but they see a free individual, it's gonna scare 'em." -- George Hanson, Easy Rider, 1969.
Rocky Mountain Varmint Hunter
Posts: 2676 | From: Salt Lake City, UT | Registered: Jan 2003
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92soggy
Knows what it's all about
Member # 4362
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posted February 07, 2016 08:25 AM
Well I tried smoothing the ejector hole out a little, didn't seem help the ejector marks much. Guess when it comes time for a new barrel I will have the gunsmith look it over.
Took it up to 32.7 grs varget today and the primer edges still looked nice and bolt lift was good.
Thank you very much sir, I was beginning to think major barrel problems like my brother had on his .17, glad it ain't that.
Posts: 39 | From: Washington | Registered: Mar 2013
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Leonard
HMFIC
Member # 2
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posted February 07, 2016 10:05 AM
So, after all this measuring and numbers, this boils down to a sloppy firing pin hole? I don't know how I missed it in the clutter?
Good hunting. El Bee
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EL BEE Knows It All and Done It All.
Don't piss me off!
Posts: 31465 | From: Upland, CA | Registered: Jan 2003
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92soggy
Knows what it's all about
Member # 4362
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posted February 07, 2016 01:03 PM
Sloppy firing pin hole, sloppy ejector hole, and a hacked up firing pin is the final diagnosis. Guess I need a PTG bolt.
Posts: 39 | From: Washington | Registered: Mar 2013
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knockemdown
Our staff photo editing Guru, par excellence
Member # 3588
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posted February 08, 2016 10:04 AM
IMHO, send that bolt to Mr. Greg Tannel & have him do this:
VIDEO linky
WEB page linky
Posts: 2202 | From: behind fascist lines | Registered: Mar 2010
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DAA
Utah/Promoted WESTERN REGIONAL Hunt Director
Member # 11
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posted February 08, 2016 10:33 AM
I've had him do several. Would do the same again too.
- DAA
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"Oh yeah, they're gonna talk to you, and talk to you, and talk to you about individual freedom, but they see a free individual, it's gonna scare 'em." -- George Hanson, Easy Rider, 1969.
Rocky Mountain Varmint Hunter
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92soggy
Knows what it's all about
Member # 4362
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posted February 08, 2016 11:50 AM
Yeah I'm just wondering about getting that ejector hole cleaned up, it bothers me having those marks on there.
Posts: 39 | From: Washington | Registered: Mar 2013
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knockemdown
Our staff photo editing Guru, par excellence
Member # 3588
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posted February 08, 2016 12:10 PM
Greg will take care of it/you...
Posts: 2202 | From: behind fascist lines | Registered: Mar 2010
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