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Old January 27, 2020, 12:54 PM   #276
stagpanther
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Curiously watching this thread stag. Enjoy your work and I really like the idea of the .350L. Ready to ditch my .450BM and .450Corvette to switch to the L, but I will be patient. I jumped on the .224V too soon and frankly, it really does not do much more than my 5.56Nato pressure loaded match ammo from the 223Wylde chambered guns. Sold my original and will be unloading the JP barrel kit instead of building one up.
I wouldn't worry about it in a bolt-action rifle that is assembled compliant with ptg's gages. Should be a simple call to the manufacturer prior to buying one. The auto loader world is a bit more of the "Wild West" as they are probably--or should I say the shooting public is--working out the foibles (224 valk deja vu) and kinks. If you stack the tolerances enough, get the right (wrong) extension configuration and combine it with a cartridge and/or brass with lack of head support--it's a toss of the dice IMO.
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Old January 27, 2020, 02:54 PM   #277
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Yeah, I want it in an AR15. Then again, I might just distill all the info and run a batch of .350L barrels myself for the AR15 that solves the problems. Guess that is a benefit of running a barrel company.
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Old January 27, 2020, 03:34 PM   #278
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That sounds cool! Let me know when you do--I might order a barrel from you. I have occasionally increased the radius (diameter, not depth) of the chamber chamfered opening to allow better ingress of the larger pistol bullets which can hang on the chamber wall at enough of an angle sometimes. That could have been the strategy of the opening on my barrel (I didn't touch it) by the manufacturer. I think a max headspace closer to 1.715 or would like be the way to go for an AR. For some reason mehavey still hasn't answered my burning curiosity for what the headspace is for his CMMG.
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Old January 27, 2020, 06:40 PM   #279
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Mainly because if it ain't broke.... OK, I'll get around to pulling the extractor and shimming a case (one of these days)
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thinking the cartridge possibly went into battery with the rim in front of the extractor
How could the bolt close in that condition? One thing about the Stoner design (and unlike Garand's) is that the bolt's gotta be pretty-well fully rotated before the firing pin will protrude far enough to ignite the primer.
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Old January 27, 2020, 06:55 PM   #280
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1.715" barely closes with feel
Likely 1.713 given tape compression.

Last edited by mehavey; January 27, 2020 at 07:20 PM.
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Old January 27, 2020, 08:14 PM   #281
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1.715" barely closes with feel
Likely 1.713 given tape compression.
Done with a case?--the ptg gage is a very good one--probably not 1.713 would be my guess--so I'm calling it 1.714--which in turn means CMMG "did it right."
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How could the bolt close in that condition? One thing about the Stoner design (and unlike Garand's) is that the bolt's gotta be pretty-well fully rotated before the firing pin will protrude far enough to ignite the primer.
I've seen too many cases with rims bent--especially the failed or bulge cases--that I can't come up with an alternative explanation. I'd be glad to hear one if you have suggestions. The firing pin clearance is a very good point--forgot about that. Still there must be some kind of asymmetric pressure on case rim upon ignition--it is consistent in all the cases with bulges. The only other factor I can keep coming back to is the overall headspace "slack."

Here's the fired hornady AW case--it looks very much like your handload bulged case.

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Last edited by stagpanther; January 28, 2020 at 07:56 PM.
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Old February 5, 2020, 12:51 PM   #282
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Postmortem

I've determined the barrel configuration is IMO inherently unsafe. Optics Planet who I bought the barrel from refuses to to take it back, insists I have to settle with Faxon. I've tried several times getting through with text and phone messages to Faxon but no response so far. I'm not even so much concerned about getting my money back as I am that others might blow their guns up if their barrel is like mine.
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Old February 10, 2020, 08:01 AM   #283
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Old March 21, 2020, 10:09 AM   #284
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born again

Got back from a lengthy trip--though it was cut short due to the coronavirus thing. Awaiting me at the post office was a new replacement 350L barrel from the fine folks at Faxon--quick headspace check showed that it passed with flying colors. It's still winter cold here and blowing strong, but I'll try to do a basic function check later today.

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Old March 21, 2020, 04:00 PM   #285
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It was blowing much too hard and my target box was waving around in the gusts, but I still got 5 shots before I bagged it. First shot to get on paper, then the next four at 36 yds. Everything went perfectly, cycling, ejection and lock back--the rifle just "feels right." The brass looks happy too. With a reddot it tips the scales at 6.5 pounds, very handy for a 20" medium contour barrel. Obviously this barrel is vastly superior to the first one and credit must be given to Faxon for working to make it right.

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Old April 1, 2020, 04:40 AM   #286
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Just when I thought I had it made!

Today I tried some handloads using Barnes Tac XP pistol bullets. No matter what people say, the 350 legend is a 9mm rifle, I think of it as the 9mm Viagra.

I was getting intermittent failure to feed with the bullet nose jamming. Took a look inside and sure enough Faxon had not put the ramps on their extension, though they had machined off the middle lower lug, a la larger pistol bullet barrels like the 458 socom. Got a little grinding to do.

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Old April 1, 2020, 10:14 AM   #287
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Yep. I had to do the same when I made my 450Corvette barrel. Had a stock extension and a .45 caliber blank. Jigs help.

I seated a bullet in a case, dipped it in paint and touched the ramp. When I was done profiling the ramp, polished it glass smooth.
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Old April 1, 2020, 01:22 PM   #288
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Good idea.
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Old April 5, 2020, 06:29 AM   #289
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I ended up taking the extension all the way down where it's flush with the receiver's ramps. I did this mainly because I shoot a wide variety of 9mm pistol bullets, including many which are FN's and loaded to short COL's. I bought many thousands of them from RMR and have an endless supply of them for all my 9mm needs.

The 350 legend is nothing but a higher velocity 9mm cartridge IMO, I'm not even going to waste any more of my time messing with so-called 30-30 equivalent loads. It's a 9mm Luger rifling--and as such I'm going to keep my bullet selection to 9mm pistol bullets for best overall performance; probably in the 115 to 147 grain range. Here are RMR's 124 gr jacketed FN's ready for testing.

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Old April 5, 2020, 07:42 AM   #290
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I could swear we've had this discussion before

SAAMI Bore/Groove/Twist/Area
9mm LUG = 0.346/0.355/10/0.967insq
357 MAG = 0.346/0.355"/18/0.969insq
350 LEG = 0.346/0.355"/16/0.967insq

BARREL BOTTOM LINE(s): 9mm = 357M = 350L
No practical difference as far as SAAMI's concerned, save the 9mm's considerably faster twist

As to performance (CMMG upper), it's running 1" groups with the Speer 180 HotCors (LEE sized to 356/7),
and "not-too-dissimilar" groups with cast Accurate 36-180LGs, Lee358-200RF, and SAECO 352-240s.

Once I switched to Winchester brass & the CMMG upper -- it's fed, run, performed perfectly/no complaints.
(It ain't no 35 Whelan, but it's a whole lot more than the 357MAG/MAX)


.

Last edited by mehavey; April 5, 2020 at 08:11 AM.
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Old April 5, 2020, 09:29 AM   #291
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Yup--we have discussed this before. ; ) I've shot fairly small groups at 100 yds also with the rifle bullets--but have found very small variables can induce HUGE variation in consistency; I personally decided it's not what I would use with confidence unless I knew exactly the performance parameters and repeated them exactly under hunting conditions--if that's what I was using its for. Not for me. Personal decision.
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