350 Legend and Cast Boolits

[Oldfeller]

Got to the range today. Back is sore, but in a good way. Right hand is sore, but my right hand is victorious again, kinda.

I shot 10 yard standard pistol target with a .40 S&W cartridge using 170 grain FBI loads at 25 yards --- when heck, I couldn't even see where the shots were landing on the man sized target.

Yep, my eyes have gotten that bad. Really, really bad.

When I walked up I was pleased to see I had made an 8" group at 25 yards and every hit was inside the fatal FBI zone.

And yes, I am aware that if you pot somebody from 25 yards that is grounds for some enthusiastic liberal DA to charge you with something ranging from manslaughter to 2nd degree murder since you could have let him run away as it is common knowledge that pistols can't hit you or anything else at 25 and 50 yards ...... (wrong)



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In my Range Diary I noted the 25 yard and 50 yard dispersion pattern of the 000 buckshot triple ball load. 4 inches at 25 yards and 8-10 inches at 50 yards with an overall drop of 6" between the two distances.

HOWEVER, my notes also say that the load is considered FAILED because the ball form will not reliably load the assembled round into the chamber, the OAL of the ball based round is way way way too short and the loaded round tilts and jams on the way into the chamber, and the action pressure & gas volume half way down the barrel is very very low (it won't cycle the bolt carrier back to lock the action) and yet the initial firing pressure even using the slower BLC-2 powder is still too high judging from the severe primer flattening that was seen on the fired rounds. I conclude that the 210 grain weight of the blue bullet train is too too much, simply too too much for an AR type action as it does not leave any free room for the initial powder expansion, lacks gas volume, has low fps and really won't work the AR action very well.

Somebody who has a bolt action Legend could still use the things, I guess.

I think I am upsetting the soft nose of the air dropped soft slugs when stuffing the case full of powder and bullet. My 200 grain blue pills are running too fat on the nose about 20% of the time and all of them need some form of post assembly nose sizing such that they will load better.

On top of this, removed jams show hard hits on the locking lug ramp area that left significant marring on the bullet nose and this stopped the action from rotating and locking properly when the marred area got into the throat. I need to thin up the powder coating some and seat the bullet deeper, or else open the throat up a little more in the barrel. I also sense I am chasing my tail here again as the bullet damage that takes place when the nose hits the ramp area over the splines is a sporadic, random damage item ...... this sounds like a classic tail chase thing to me, really.

BLC-2 speed WC846 powder was simply too slow of a powder for the Legend, it burned incompletely and left lots of ash mummies in the barrel. Varying the bullet weight and charge weight didn't help the mummies much and the ash mummies still remained in the barrel and down inside the carrier --- the WC846 stuff is just plain too slow for the 350 Legend.

Best powder seen out of my powder closet was AA#9 speed WC820, it burned clean and left a minimal ash residue in the barrel. 158 grain pistol bullets and 200 grain rifle bullet loads actually liked the same range of charge weight (a 1.3cc dipper full at ~ approx. 20 grains ~) which is a moderate primer pressure load with 158 grain bullet weights and a mild primer flattening load at 200 grain rifle bullet weights. In both cases, the AR's action was smooth and there were no jam ups.

Best accuracy load seen was 1.3cc (20 grains) of AA#9 speed WC820 behind a 200 grain bullet, multiple 1" to 1.5" 3 shot groups at 50 yards were done during sight in. The wide meplat 158 gain bullet was also fairly good at 2.5" groups using the same 1.3cc (20 grain) loads.

Going hotter with 1.6cc (24 grains) of AA#9 speed WC820 behind a 200 grain bullet yielded a very flattened primer and lower accuracy levels and a harsh abrupt action and some bullet nose deforming jam ups where the slamming action was simply too abrupt and caught the bullet up hard against the feed zone over the locking splines.

Bullet damage in loading the soft powder coated lead bullets from magazine over the splines and into the chamber seems to be a thing with the Legend .....

I made a lot of other load powder types and pressure levels that didn't do near as well as the AA#9 speed WC820 loads, all of which experiments will now get pulled down and the components recycled.

Let's repeat the double charge warning ---- use of a low volume fast burning powder that can fit two charges down inside the long deep DARK 350 Legend case is inherently dangerous.

[Oldfeller]

Got an E-Mail notice tonight from LEE that they had shipped my .388" bulge buster push through die. That was like a month early, so I am happy.

Recovered most of my early development loads, scrapping the bullets but saving the cases and the powder.

Did a detail clean of the AR-Legend, tuned the firing pin motion in the bolt carrier, it now protrudes .005" more than it did before.

(small steps here, too much here can cause multi-fire problems you know)

Gun is still breaking in, black oxide isn't even worn through on the carrier slide bearing portions yet.

Experimented with using the open base end of a 30 Carbine case sizing die as a Legend assembled round bullet nose sizer -- close but a little bit too small to do this particular job.

[P Flados]

Oldfeller,

When I was working up boolit loads for my 357AR, I had a lot of of problems with nose damage and jams. The Lee 200 was one of the worst for getting beat up. The worst cases for the Lee 200s would have the top of the meplat hit the back of the barrel just above the chamber. Better but not good was when the meplat was getting into the opening, but then the edge of the chamber would gouge the boolit just behind the meplat.

The biggest improvement to the gun would be a more optimum feed profile on the barrel extension (the part with the locking lugs). Slowly let the bolt forward to feed a round from the magazine while carefully watching the nose. To minimize nose damage, it would be ideal for the nose of the round to be centered in the opening and just inside the chamber just as the back of the round is released from the magazine. If your rounds are being pushed too high or off to one side, dremel grinding on the feed ramps would help. Note that the "factory profile" is at best optimized for pointy 350L J-words or just as likely could be a profile for a 5.56 or 300 BO.

A bigger radius on the chamber entry can help, but only if things are pretty close to good before the radius is increased.

The other thing to look for is the nose hitting just below the start of the feed ramp as it is just edging out of the magazine.

For me, my rounds are not long enough and the round is in "free flight" from the time the round is release from the mag until the nose is inside the chamber. It did not work very well at first. I eventually adjusted the feed profile and changed boolits (see below) such that the profile is able to guide the nose of the round into the chamber with no damage.

The other item to consider is boolit shape. For my 357 AR, I ended up making a custom mold to drop a 180 from one cavity and a 200 from the other cavity with an "AR Friendly" smallish meplat with smooth ogive from the meplat back to the case neck. Pictures are at post 79 of:

http://castboolits.gunloads.com/show...-Rimless)-AR15

There is more discussion at the link below. Post 91 of the link has a picture of a target where I put 6 rounds in less than 4" at 200 yards from a load that was pushing my 200s at just over 2000 fps.

https://mdws.forumchitchat.com/post/...5573?trail=100

I checked and my boolits should work in a 350L even with the longer case.

[Oldfeller]

Push through .388" bulge buster die showed up from LEE. As well as I could tell, they built it to what I asked for --- the sizing zone is snug to tight on a .388" pin gage.

I pushed through all my Graf's brass and laid aside all the ones that felt tight or took extra pressure to process. This tight stuff amounted to 20% of all the range brass I bought.

Looking at the sizing die marks on the cases, there sure are a lot of out of round chambers out there. There are also some chambers where the feeding ramp of the gun is showing up clearly on the fired cases.

Next new knowledge was the sheer amount of spring back that these malformed cases still have the ability to do. Die is .388", case nominal at that area of un-abused brass is .388", worst case over expansion is .3925. Worst case "ramp bulge" was .0045 which was expressed as out of round when measuring it.

Issue remaining is that the spring back inherent in the brass gives you back a lot of the error you started out with. Re-sizing the cases with the push through bulge buster simply reduces the amount of the remaining error down some --- removing only .0005" to .0015" of the original error (you never get rid of it totally).

What may work better is removing stock from the loading face of your full length sizer die and removing stock from the face of your shell holder. By doing so you are making a small base sizing die out of your stock 350 Legend full length die.

Doing this grinding material removal is a lot cheaper than ordering a custom push through sizer so make yourself a poor man's small base full length sizer die and save the money on the "mostly failed" push through bulge buster die idea.

[P Flados]

Oldfeller,

Did you see if your gun can easily chamber all of the ammo you have run through the 0.388 sizer? If it will chamber and extract them without extra effort, I would be tempted to load and fire a few to see how they work.

[Oldfeller]

I already broke down all the old rounds that didn't perform as well as the best two and recovered the components already.

The string of 3 triple aught buckshot rounds cannot be broken down (far too tight and the balls are pocket recessed in the taper sized brass too firmly for an impact puller to move them). Whenever I have the time and motivation at the range I will simply shoot them up one at a time until they are gone.

Or simply give them to somebody with a bolt action gun, which is more likely.

I can load and unload the "push through" Winchester standard cases fine, it is the homemade from 5.56 brass that isn't able to be totally recovered by push through sizing.

I was disappointed in the hardened brass spring back effects making the push through resizing far less effective than it might have been.

By "small basing" your full length 350 Legend resizing die you can repeatedly "taper crush" the bulge zones at the correct angle while simply processing your brass several times normally just doing the de-priming and normal finished sizing that you would normally do for any automatic rifle.

That is the theory, anyway. On the far end you will collapse the mouth a little extra (proportionally the same movement) but nothing that the powder through expander die won't correct for you automatically.

And yes, I will eventually do it and post just how much to take off the end of the standard full length sizer die. Just measuring it with a caliper says that the case taper is a simple cone ending in .388" so assuming you can project off the case drawings you can small base the Legend case with a reasonable shortening of the full length sizer die body and a very mild (and short) re-radiusing of the opening.

Bolt guns can likely eat these bulge forms and correct them naturally as they use relatively large loading crush pressures and have some large extraction forces available to them as well. Firing normal pressure cast rounds will spank the case bulges in the chamber steel, tending to remove the bulging over time and multiple re-loadings.

[Oldfeller]

Next puzzlement .....

We know the boy tweeked the back side of his firing pin hole in the bolt head to make it strike .005" deeper.

We know he has short light strike issues on his 5.56 reformed brass, because it is short in his chamber.

He can do a good bit more tuning with the firing pin in the bolt head, but he won't do that he tries what he has now. Slam fires are out there, somewhere, jest a waiting for him and he knows it ......

We know his reformed 5.56 brass is starting out at .030" short, give or take a bit. A firing or two would make it longer, possibly to within functional dimensions.

We know he likes to cheat and he loves a good trick (keeps a little black book of them, he does).

This is more trouble than it is worth. Functionally replaced by firing pin extension tuning.

So what is this and what can it do as a useful trick ?????

[Oldfeller]

I think they need a hint.

A paper cutter with a stop can make a bunch of .040"-.060" wide bands right quick like. Drop them around the bullet and they slide down until the case neck stops them.

A little hair dryer heat and they snug up just dandy.

DON'T FORGET THE BANDS WILL SHRINK IN WIDTH WHEN YOU HAIR DRYER THEM ON THE BULLET.

They get slam squished some upon loading, but they will keep the bolt head & extractor properly engaged to the case head extractor groove just dandy.

And upon firing they will shrink some more and get caught up in the gas flow and exit the barrel. Or become one with the powder fouling, whichever. It is very rare to see one again.

This is more trouble than it is worth. Functionally replaced by firing pin extension tuning.

[Oldfeller]

Using the paper cutter is just too cumbersome as it is too large a tool and the cut to size heat shrink bands are really quite small.

Here is a better tool that is based upon a pair of cheap scissors and a little tab of stiff backed velcro material that I had lying around handy.



As you can see, the stop is sized to fit the job and adds no weight to a pair of sharp scissors.

This is more trouble than it is worth. Functionally replaced by firing pin extension tuning.


This shows the width control which is equal to the scissors blade thickness. The raw band is cut to be .060" wide but it shrinks in width when you settle it in place and heat it with a common hair dryer.

Mine wind up between .030" and .040" wide after getting hit with the hair dryer and then they get loading scrunched to be a bit shorter as the material gets accordion jammed into the "short case" space in the chamber.

What happens after firing is anyone's guess, I haven't found one yet to say.

Using this tool and a common zip lock baggie you can quickly save a couple of thousand cut to width bands for future use. Hopefully they won't be needed for that long as your short 5.56 based brass will grow in length after you fire it a few times.

[Oldfeller]

Monday, revisited the bolt group again, this time going after maximum firing pin protrusion.

Got up to .055" firing pin protrusion before it started to get sticky on me at the end of firing pin travel, then spent over an hour with 8 micron diamond paste and some 220 and 400 grit wet or dry paper working the various shoulder areas to get the firing pin to be completely free moving again (and get the pin end of motion "stopping action" balanced between the large flat flange and the tiny firing pin nose taper and the larger taper in the middle of the pin's length).

Picked up another .005 of primer protrusion getting rid of the "sticky" so at .060" primer pin protrusion I am now in the short end of the ballpark of igniting my 5.56 reformed brass "as is".

My "failure to fire --- light strike issues" went way way way way down. What also happened was my estimation of primer flattening pressure signs got changed as well. All I really had before were a bunch of short, light strikes ---- not a bunch of "flattened primers" ---- so I am currently re-evaluating my load pressure ranges with newly fired cases.

Next, I took apart and cleaned the extractor hook spring and read up on issues associated with too strong and too weak of an extractor hook spring.

My extractor spring extended length exceeds .800" right now and the extractor motion of my stuff seems to tend to be the "too strong" side of things rather than too weak side, but I also am mindful of the recommendation to do nothing to it except keep it clean until the initial break in 500 rounds have been fired.

"Your extractor spring will settle in length" is a simple statement that requires a little bit of patience to check, but I can do that.

Extraction per se has not been an issue since I lengthened the chamber throat to allow the very lightly engraved bullets to be extracted by the bolt carrier handle.

My theory on the high extractor spring pressure is that I am simply fighting too hard to get the extractor up and over the case head to the point it really isn't happening until the case gets stopped hard, and as a result I am over-driving the case all the way to the bitter end of the chamber before the hook goes over the rim and seats.

Less extractor hook pressure would help here, I think. I would expect a proper spring tension would allow the hook to ride over and settle due to the large amounts of bullet mass / inertia and the mild interference of the case in the chamber taper.

[cwlongshot]

All this reads like allot of Rigmarole that simply factory cases would solve...

Also as it pertains to primers and pressure. More proof that primers alone are a very poor indicator of relative pressure.

CW

[mehavey]

If y'all want a handle on pressure in a cartridge such as this -- no data at all for cast projectiles -- I suggest QuickLoad and (very) sharp attention to chronograph results extrapolated back to effective burn rates ... and thence to implied pressures.

. . . which is what I'm dealing with now w/ an AR_Legend as I build up a data reference.

FWIW: Both the SAECO #352 (358-245gr FNGC) 2.235" and the LEE 358-200RF (FNFC) 2.165" are excellent, and at 0.358" function quite reliably using full-up cases of AA2015 and V-N120 respectively.

Now just playing between Lee push-through/thin ALOX coating vs conventional lubrisizer/50-50.
Spotless bores in both cases upon a single dry patch.

[Oldfeller]

All this reads like allot of Rigmarole that simply factory cases would solve...

Also as it pertains to primers and pressure. More proof that primers alone are a very poor indicator of relative pressure.

CW

He's right of course, that's why I recommend to everybody (and I bought some myself) once fired range brass cases from Graf's.

You can say with complete surety that you do not want to make 350 Legend cases using 5.56 brass, you have seen the mess it really is from start to finish.

Extend your criticism a bit, and aim it at the 350 Legend as a whole cartridge and rifle set up ......

All this reads like allot of Rigmarole that a factory 35 Remington would simply solve .....

Yes, the 350 Legend really is a bit of a kludge of a cartridge. I just ordered 4 each thirty round Magpul .223 magazines, magazines that are made of plastic so I can trim the front ribs out of them with a homemade plastic scraper so I can actually have me a large capacity magazine for the 350 Legend as none of such things are made yet by anybody at this point in time.

If you would simply read this thread from the beginning having a piece of paper and a pen at hand, you could write up a whole bevy of reasons the non-Winchester factory round 350 Legend is not something the casual reloader should ever attempt.

A casual reloader that gets in as deep as Mehavey or me is still doomed to still drown in all the "you can't buy that piece yet" issues that still remain.

The folks who actually carried through to completed fully functional 350 Legend auto-loading guns that are shooting powder coated lead bullets are really quite rare.

However, for someone who likes to think, invent and to overcome obstacles can have a lot more fun with a gun like this than any normal gun .......



....... ouch, ouch, ouch, ouch, ouch, ....... boy I'm having so much fun I can't hardly stand it .......


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Mehavey, what upper/barrel/chamber are you using? The stock Legend SAMMI chamber simply won't accept a .358" bullet into the throat any at all, not a smidge of it, I had to lengthen my chamber's throat just to load a intentionally reduced to .3565" during push through sizing powder coated LEE 200 grain slug.

[cwlongshot]

I made two mage for mine before I had a gun! :

Tip for ya, pick up a couple Foam or cardboard nail files. They work perfectly for smoothing out the insides of the mag so the follower rides smoothly! I also finished with a abruptly nose up profile. I was worried, But its proven to work to the last shot. I still occasionally have a misfeed on last bullet in magazine. Unsure why. Does not seem to matter if I load 9/8/6/3... but If I load one it feeds off the mag perfectly. Ooh well is not going to war, Im fine with that!

Ooh 4227 and a powder coated 190 Ranch dog bullet shoots about 1” @ 50 and nice round 2” @ 100 in my gun. At a 1750 fps velocity.

CW

[mehavey]

Oldfeller: The upper is a www.Durkintactical.com, and as you (and a lot of us) found out, the SAAMI Legend chamber has very little/very tight freebore:
In fact, somewhere between 80-90 thou long max and 0.357" at that (if SAAMI is to be believed).


But while the Durkin barely gives me that 80-100"-thou in length, it apparently does give me 0.358" in throat diameter.

NOTE: I've tried sizing down to .357 in the trials, but it likes .358 better.
But woe betide that any straight shank get too far out from the mouth.
(Hornady bullets of any type are bad that way.)

[Oldfeller]

To get more reliable feeding I extended my bullet throat more and lapped my throat to .3575"(case mouth) - .3565" (end of throat). Here is the image of the original .3565" lap configuration.

.3575" diameter lap

I have recently charged the lap with some larger grit that I lapping plate rolled down to a nice round .358" measured diameter and am waiting for some sort of trip decision point to happen to decide whether I am going to use it or not.

Advantage to opening the throat to .358" size is that I can load some jacketed .358" bullets way on out in the magazine and I can still crush seat the mouth taper zone containing the bullet shank using the full length sizer die to maintain the neck diameter zone over the fatter bullet to maintain chamber loading and bullet release clearance.

Downside will be a loss in accuracy with jacketed vs powder coated lead ......

It will feed better, that I can be fairly confident of that .....




Here is a fresh pic of the larger grit charged lap. When you caliper it, you get .358" to .3585" but we know the larger grit will break down in use and it will lap smaller at the tip end than it measures now.

[tomme boy]

Good luck on the mags. C-Products said high caps will be out this Nov. at some point. I will wait till then. The Pmags are a pain in the rear end to make reliable. Everyone has trouble with them. All you have to do is get a 300 blk mag then lower the front rib a little. The 300 mags already have the rib taken out.

[Oldfeller]

I think they are promising a 20 rounder and I wanted a 30 round capacity. Also, I wanted to pay $9.75 for the mags, not $35 .....

[cwlongshot]

I did ten rounders, cause its real hard to remove that rib from such a long mag. The ten rounders are easier that way and Ill never have needs or wants for more. As stated its never going “to war”. A couple tens will be more than enough, to ward off the fiercest hog charge ill see.

CW

[Oldfeller]

I just ordered 4 each thirty round Magpul .223 magazines, magazines that are made of plastic so I can trim the front ribs out of them with a homemade plastic scraper so I can actually have me a large 30 round capacity magazine for the 350 Legend as any of such things are not made yet by anybody at this point in time.

Tommie, I don't willingly buy Pmags brand for anything, I think I got bit by them once long ago during my Glock days.

I was actually unaware that Magpul and Pmag were made by the same folks now-a-days, but sure enough, Magpul Co. makes the Pmag brand in a whole bunch of different AR-15 capacities, versions and rib structures and plastic types stretching back over lo these many many years.

Magpul also makes a Magpul brand magazine which is supposedly different, better stuff ......

Magpul magazines are supposedly "good to go" for AR-15 uses and they go on sale for cheap all the time.

I hope what actually comes in the mail next week says Magpul on it and not Pmag. But generally, I am not that lucky.

And heck, if it was easy it wouldn't be for a 350 Legend, now would it?

Think of an old wood based shave plane, now make it thin enough to go through the two end openings in a magazine with the floor plate and guts all removed. Shave off a couple of thou of plastic off the rib per stroke so it will be nice and easy to do.