AR disease strikes again

[mehavey]

No issues there (again the closer 0.010" tolerance works in your favor) to ensure/force extractor over the rim.

The only "real" issue might be bolt failure to completely rotate closed if the chamber's short/case long outside of both specs simultaneously. And even there, the AR bolt design's fail-safe of not allowing firing pin protrusion unless it has rotated to at least safe lug-engagement comes into play.

Stoner builded far better than he knew at the time -- and that we appreciate even now.





ps: clean/slick/residual case lube is always your friend.

[P Flados]

With the Winchester QC problems, folks are having headspace problems.

With too much headspace (short brass and/or long chamber), weak primer hits can occur. Some gun / ammo combinations may work with excessive headspace due to the extractor holding the case rim. However, relying on extractors is not nearly as positive as proper case length and chamber dimensions.

With cases that are too long for a given chamber, the bolt will not fully close without compressing the case or squeezing the end of the case past the headspace step in the the chamber. If an AR is self feeding ammo, the inertia of the bolt can be enough to do just the above. Bolt actions can easily do it with heavy handed operation. If the end of the case is pushed in too far, the bullet will not release properly. Grossly flattened primers and split cases with factory ammo have been caused by Winchester brass that is too long.

Failure to fire problems are occurring. This is probably mostly too short, but can be from too long in an AR if the case is stopping the bolt from fully rotating into the locked position.

Fired cases of factory ammo are showing overpressure sings and/or gross damage.

People are measuring factory ammo cases as out of spec for length in both directions.

[mehavey]

So far.... no issues with Winchester/Federal Comm'l;
and No issues w/ Handloaded Starline brass

[stagpanther]

Keep up the good work.

[reynolds357]

Originally Posted by stagpanther

Thanks meheavy; I'll look that up. I already have other 358 caliber cartridges so am well stocked in bullets but they tend to be heavier ones in 200 to 225 gr, though I do have some 180 tsx's (which I suspect would have opening velocity issues in the legend). Winnie's bullets look a lot like hotcores

Oh--I also see you're well down the research path in your links, I like that point blank range, really 200 yds is perfect for New England woods purposes. This cartridge may go the way of the 25-45 sharps (which I also have and also shoots hotcores extremely well), I'm just curious to see how it shoots in an AR.

You got some pretty heady performance for a small capacity 16" barrel 357--well done! I was wondering why your labradar dropped tracking at 90 yds--but it has a "weak spot" for pistol like bullets at the 1700 fps transition (or maybe you just wanted those 5 inputs alone?)

The bullets made for 350 Legend greatly simplify the process.

[stagpanther]

The bullets made for 350 Legend greatly simplify the process.

I've got em! I have all the components to start reloading--but I thought maybe I should wait till the gun parts get here and I put it together and get some measurements before committing.

[stagpanther]

So far.... no issues with Winchester/Federal Comm'l;
and No issues w/ Handloaded Starline brass

My 357 bullet sizing die just came in--I haven't tried it yet, but the first question that comes to my mind is how do you keep the noses of the bullets from deforming when pushing the following bullet through the die? Looks like you "stack em" through.

[mehavey]

When the die is screwed in/down to just clear the ram, the first bullet actually clears the sizing section/goes loose inside the middle of the die when pushed through. Second bullet sees no resistance from it at all.

Use/rub the "barest bit" of case lube/ Imperial wax on your thumb/forefinger as you pick the bullets up to size them.

[stagpanther]

When the die is screwed in/down to just clear the ram, the first bullet actually clears the sizing section/goes loose inside the middle of the die when pushed through. Second bullet sees no resistance from it at all.

In other words the interior of the die tapers wider after the ram does it's thing? I thought that would likely be the case--but I thought better to ask you first. thanks.: )

[mehavey]

When finished sizing a handful of bullets, all but two will clear the top of the die/fall out.
Unscrew the die/turn upside down and those last two will fall out loose as well.

[stagpanther]

When finished sizing a handful of bullets, all but two will clear the top of the die/fall out.
Unscrew the die/turn upside down and those last two will fall out loose as well.

I'm not worried about that--I just didn't know how/if the interior was tapered. Have you noticed any changes dimensionally in the 180 hotcores after sizing them?

[mehavey]

Now you made go a size a coupla dozen.

Because of the way the Lee die is close-fitting/bottom-push, all the happens is it goes from 358 --> 357 and maybe (barely maybe) 0.0005 (three zeroes) longer by my 4-decimal place calipers.

The Legend's throat is short. Mine allowed a full 2.26" OAL w/o sticking anything w/ the Speer 180's near-ideal ogive curvature. Check-6 trial/error on yours when able.

[stagpanther]

Now you made go a size a coupla dozen.

Becuase of the way the Lee die is close-fitting/bottom-push, all the happens is it goes from 358 --> 357 and maybe (barely maybe) 0.0005 (three zeroes) longer by my 4-decimal place calibers.

Just curious Since the bullet is hot-bonded to the jacket during manufacture I was curious about whether the "squeeze" had any effect on the internal structure too.

[mehavey]

If it had any (internal/structural) effect, it sure didn't show when spun up to 95,000 RPM

[stagpanther]

If it had any (internal/structural) effect, it sure didn't show when spun up to 95,000 RPM

You got one of those concentricity balance machines?

Meanwhile, the trail has gone cold on most of the parts I ordered, still waiting on most of them, they were due by Friday and still say scheduled to be delivered by then--but it looks like they haven't been scanned in since the middle of the week.

One Hazmat package came in that literally looked like it had been run over by a truck--the box was crushed and split on all seams with gashes/holes. Considering the pounds of black powder that was inside it--I wonder if anyone actually pays attention to the warnings on the boxes.

[mehavey]

concentricity balance machines

Yeah,
15" engine / 16 twist / 2,100fps with a 300-ft arbor pin marker at the end.

[stagpanther]

LOL

[stagpanther]

The barrel finally made it today--I can remove it from the MIA list. Almost all of the other parts MIA involve hand-offs to the USPS. Coincidence?

The Faxon barrel looks very well made, I like the fact that took some of the weight off by putting a contour to the barrel. A bit mystified by the fingernail paint key marks on extension--but checking it the extension pin is perfectly lined up with gas port.

[stagpanther]

Further quick examination and it became immediately apparent to me what the headspace fuss is all about without even taking measurements-- notice that the case head area from the base of the case to the rim face is much deeper on the 350 L than a standard 5.56, particularly the size of the extractor groove.



Looking at the extension, you can see that they added a significant radius to the chamber face (from what I can tell from dropping a cartridge in, the chamber support ends at the base of the case/top of the case head. Along with the single machined ramp at the bottom of the extension--which is what I see usually on single-stack big bore AR's--I'm assuming this is to allow for more reliable chambering of cartridges that are ingressing at an angle. I rarely see machined radius that big except on pistol cartridge carbines.

[mehavey]

So we're saying the case/chamber face characteristics appears as a good things (?)

[stagpanther]

So we're saying the case/chamber face characteristics appears as a good things (?)

Keep in mind I have 0 experience with this cartridge--but at first blush this strikes me as unusual. Have you seen any signs in your brass that's been fired multiple times of anything unusual in the case head or web area?

[mehavey]

Fourth cycle in a half-dozen i'm using as high-pressure primer-pocket tests.
Nothing unusual yet. (minimal case growth too)

[stagpanther]

Fourth cycle in a half-dozen i'm using as high-pressure primer-pocket tests.
Nothing unusual yet. (minimal case growth too)

Good to know.

[mehavey]

-- yet --

[mehavey]

It likes heavy cast too . . .



(My daily two-shots-only/end-of-day range-run therapy)