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Moleman-
07-27-2016, 09:10 PM
Here are some 357AR (MaxRimless) cases made from 5.56 LC-13 brass and thought I'd show the steps. A couple of guys have made the cases from 357Max brass which just involves changing the rimmed case to rimless, but I like using cheap 223 and 556 brass. So here's the steps:

1. trim to 1.640"-1.650" and debur

2. anneal

3. lube inside the case and expand case mouth with skinny expander

4. expand case body with blunt expander

5. resize

6. roll case shoulder wrinkle away (optional)

7. turn necks/ream to .0105" case wall thickness

8. trim to final length 1.595" and tumble

9. load/shoot


This method seems to work very well as I had no split cases out of the 40 or so I formed in this batch. Hunting season is just around the corner and I figure I'll make another 100 or so since my son is also shooting them now. Usually I've had around 5-10 cases split out of 100 when using once? fired range mystery brass. Any flaw in the case mouth of the parent case will result in a split since they are getting expanded up so much. The initial trim and debur really cuts down on losses. This batch of LC-13 cases probably would of been fine without turning/reaming, but I've had others like FC cases that wouldn't chamber without turning so I just turn them all. Really all you're reaming or turning off is where the base of the bullet would be. The two expander stems are made from a bolt (it's quick and easy) and some hardened drill rod. They just fit into a Lee 38-357 powder through die body

Michael J. Spangler
07-27-2016, 09:57 PM
Subscribed for updates.
Will you get into any details on the AR build in this thread?
I'm thinking of changing my AR over to 300BO because it likes cast. I bet this would be a much better chambering.


Sent from my iPhone using Tapatalk

PaulG67
07-27-2016, 10:56 PM
Now that is something that I would love to do in an AR, HOWEVER I live in Massa!@#$%^&*()_+_)(*@#^&*&^$#!@^&*(_)(*chusetts and it recently became illegal for me to enjoy my hobby in such a way.

Michael J. Spangler
07-27-2016, 11:13 PM
I'm with you Paul. Fingers crossed and lots of phone calls and emails sent. We can beat this one. Will you be at the state house Saturday?
Not to hijack but goal has an announcement tomorrow and will be speaking on Howie Carr's show.

Hopefully we can come back to this thread and make moleman proud when we show off our 357ars


Sent from my iPhone using Tapatalk

Moleman-
07-27-2016, 11:21 PM
I have enough pics to do a quick 357AR build thread in the "special project" area if it would be appropriate to put it there. I've only ever shot one type of cast bullet out of it and they shot well even though they weren't perhaps the best profile for a semiauto as the corners of the flat tips get rounded off going up the feed ramp. I'm working on a 44BGM AR10 to use this fall and many of the build steps are the same for each rifle.

PaulG67
07-27-2016, 11:26 PM
I have attended several G.O.A.L. rallies in the past but will not be able to attend this one. I am having a health problem that will put me in Beth Israel hospital for about two weeks in the near future. Funny I will be in Boston just not the right time.

badgeredd
07-28-2016, 03:28 PM
I have enough pics to do a quick 357AR build thread in the "special project" area if it would be appropriate to put it there. I've only ever shot one type of cast bullet out of it and they shot well even though they weren't perhaps the best profile for a semiauto as the corners of the flat tips get rounded off going up the feed ramp. I'm working on a 44BGM AR10 to use this fall and many of the build steps are the same for each rifle.


It would be absolutely appropriate to put up a post in the Special Projects" area. I will be watching for it.

Moleman-
07-28-2016, 04:14 PM
It would be absolutely appropriate to put up a post in the Special Projects" area. I will be watching for it.

Got it put up http://castboolits.gunloads.com/showthread.php?312313-357AR-(Max-Rimless)-AR15

SSGOldfart
07-28-2016, 07:57 PM
Human this is a idea that piques my interest to. I have Mike Bellum cutting a camber for shooting 357 Maximum Rimless
In a TC now,which is very close to your 357AT,I'd like to see your 44BGM AR10.

Moleman-
07-28-2016, 10:48 PM
I looked at Bellum's site quite a bit when while making a test barrel to see if I could even get one to feed. It, and all of the links in it are a good read for someone with a 357Max. Still gathering parts for the 44BGM ar10. The barrel is headspaced and I started on the barrel nut wrench today. Once it's closer to being done I'll start a thread on it.

2wheelDuke
07-29-2016, 09:01 AM
Great thread (and your other one on the builds.) I know the possibility of a cut off .223 being turned into a .357 had been discussed for years, but I haven't seen much on anyone actually doing it.

I've been interested in the .300 blackout for a while now. It's a decent round, but I really feel that I got suckered a bit by the original writeups on it, namely the ones that compared it to 30-30 win and 7.62x39. Sure the blackout fills a niche that those 2 can't for people that want subsonic or short barreled performance, but that's a different issue. The blackout is adequate to hunt deer and hog in any area I can afford to go, and does allow me to run cast fairly easily in the AR platform.

This round interests me though. I've assembled AR's but I don't have the means to turn barrels and install extensions. It'd be interesting to see one or more of the companies run with this round as yet another contender for hunting with the AR.

Moleman-
07-29-2016, 10:09 AM
I also would like to see a company run with it. It's not new or fancy but it does a good job of filling the requirements of the Limited Firearms Zone in southern Michigan and is not a hard kicking rifle for smaller shooters.

nvreloader
07-29-2016, 11:20 AM
Moleman

Would it be better to anneal the case mouth/shoulder areas before,
you expand the neck/shoulder out to proper size?

Do you by any chance have a reamer chamber print for your case,
or know where I can find a chamber/reamer print?

I would believe that this case Head spaces on the case mouth, correct?

Another great use for the 223 case, never a shortage of cases.

Tia,
Don

AggieEE
07-29-2016, 12:06 PM
Question about the 44BGM. How does that compare to the 44 Automag? If the length isn't too short to work through the mags that may be interesting.

Moleman-
07-29-2016, 12:31 PM
nvreloader,
I've tried several different methods including annealing several times including between the two expanding arbors. Mostly it's the initial opening with the skinny expander that will split a once fired case at a nick or deep scratch on the neck/shoulder. Expanding up to 6mm or so first also helps a little, but not as much as trimming and deburring them first does. The above method is the one I've settled on as a good balance between time and case loss.

I made the first reamer going off of a saami print tweaked for headspacing off of the case rim and a longer throat. Actually got the useable throat way to long which I adjusted on my second reamer and added in .001" (.002" total) more chamber taper for feeding. I had Dave Manson make me a floating pilot reamer (he has his 357AR print on file). He felt there should be more chamber taper (.005") for feeding and a much shorter freebore (.075"). I chambered my pistol with the Manson reamer and used it during the 2013 deer season. Things I noticed were that it didn't feed any better or worse than my other barrels with .002"-.003" taper and the cases needed trimmed much sooner. The extra diameter from the looser chamber was letting the cases expand more which turned to extra length once the cases were resized. Perhaps if I had a custom die set made it wouldn't be an issue, but I want to keep it so it can be reloaded with an off the shelf die set. The lead bullets shown above also would not chamber in the pistol as they hit the rifling because of the shorter freebore and leade. With that in mind, I made a floating pilot reamer shown above in the wood box that I've used since with the specs below. Feeds well, chambers heavy lead bullets, shoots well, and can chamber .357" and .358" barrels.

Moleman-
07-29-2016, 12:51 PM
Question about the 44BGM. How does that compare to the 44 Automag? If the length isn't too short to work through the mags that may be interesting.

I hunted with a lower pressure version last year in a 1891 mauser. It would push 265gr bullets to around 1985fps at 37Kpsi. The higher pressure version for the ar10 can beat a 444marlin with a similar length barrel if you want to go that route. I want to get a decent feeding lead gas checked bullet mold for it at around 300-325gr and wouldn't rule out possibly as high as 350gr. I've got a lower pressure 44x1.7" planned for an ar15 that the cast bullets would also get used out of. Still gathering parts for it and haven't made a reamer for it yet.

runfiverun
07-29-2016, 09:57 PM
I have a 223 case I modified to take a 250gr 35 cal cast boolit and it is super simple to do.
it feeds from the magazine too.
it's only drawback is head spacing on the case mouth so it turns into a supersized 30 carbine.

Moleman-
07-29-2016, 11:29 PM
runfiverun, what mold are you using? I've almost ordered the NOE 200grFN which I've shot or the 245rn which seems to be a similar profile to 200gr sierra rn that feed well out of my uppers. I also saw the MP 220gr WNFT which looks like it has a smaller diameter tip which might slide through the feed ramps easier.
Headspacing off of the case mouth so far hasn't been an issue. While not ideal it helps meet the case requirements set by the DNR and allows an easy semiauto build.

runfiverun
07-30-2016, 01:08 AM
the saeco #248
the nose profile has a smaller meplat which helps feeding.
I use the same boolit in my 358 win.

anyway I decided to try making the cases and seeing if they would try to feed in the AR cause I had a couple of oopsie boolits there while I was loading them in some 357 max cases.
I just set the oal for the magazine and popped the beavertail and schunk they went right in till the boolit hit the chambers neck.

Moleman-
07-30-2016, 02:04 AM
That's heavier than I really wanted to go, but I like the profile of it. How do they do in the Max?

ubetcha
07-30-2016, 06:49 AM
Moleman
Can you give us some specs and more info on how you made the expanders. I have been collecting 223 brass every time I go to the range and I have been thinking about trying to make 357 rimless, but not sure on how to expand properly. This would be used in a Mike Bellm chambered T/C 12" 357Max bbl. I can have one of my sons make the expander's as he is in Tool and Die

.455 Webley
07-30-2016, 08:26 AM
Is anyone else amused at how close this is getting to the .351WSL?

1BIGGUN
07-30-2016, 12:26 PM
Is anyone else amused at how close this is getting to the .351WSL?

Not really the 357 AR is shorter loaded hotter has different dia bullet an uses a different rim diameter ( .373") and is MI an other states legal for deer hunting and the 351 is not . Brass is almost free if you know were to look for the 357 AR .

Sure there close but so is a 357 mag .

351WSL
The rim diameter is .407" and the head diameter is .380". Cartridge overall length is 1.90". Jacketed bullet diameter is .351", not the standard .357"-.358" used by modern .35 caliber cartridges. Size cast bullets to .352". The maximum average pressure should not exceed 39,000 psi.

Interesting round however .

Moleman-
07-30-2016, 01:29 PM
The 351WSL cartridge did come up a few years back when I was making the first reamer since it's performance is so close to 357Max. Most of the loads I've used so far are faster than book loads for 357Max since the allowable pressure is higher. There is also the 357 auto and the 357 rimless mag (223 ar15) both of which have the similar case mouth and rim diameters. Years ago someone once told me in the world of wildcats it's all likely been tried by someone at some point. I know rimless 357Max cases have been made before, and there is plenty of load data out there for hotter 357Max loads. I was just focusing this based on getting them to feed and cycle out of an ar15 while still being able to use cheap standard die sets.

SSGOldfart
07-30-2016, 02:04 PM
Even having to spring for a set of custom dies,you would still be ahead of the game with brass being available/ or make it yourself.

Moleman-
07-30-2016, 02:05 PM
Ubetcha,
I'm using them in a Lee die set, so the measurements of the threaded area may be different for your application. I also used a cheap hardware bolt with the inner head surface cleaned up so it wouldn't try to kick the head off to one side. If I were to make them again I'd just use some bar stock and knurl the tops. The threaded section is 5/8"-24tpi and 1/2" long plus the head. The stems were made of 1/2" hardened O1 drill rod and turned with a 1/2 long 5/16" stem that was pressed into the bolt head. There is a short 1/8"-3/16"section that is at 1/2" diameter to make a shoulder so the stem cannot be pushed up into the die any further in use. The top sections are the same on both expander stems so onto the differences.

The skinny expander stem is 1.65" long including the 1/8" shoulder. The top diameter is .355" and the bottom diameter is .170" with the bottom rounded off.

The blunt expander is 1.7" long including the shoulder. The top diameter is .358" and about 1.25" long. Then it tapers down to 1.45 at .3" diameter. Then tapers down again to 1.55" at .2" dia.

The corners of the tapers were rounded off and the stems were hardened and polished before they were pressed into the bolt heads. None of the diameters are really critical.

ubetcha
07-30-2016, 05:35 PM
Thanks Moleman. I will pass the info to my son and see what he can do. This caliper is fairly new to me, but have shot it in IHMSA silhouettes with out any real sight setting yet and have done fairly well. been about a 30 out of 40 targets with guess hold over. I really like this caliper. Need to spend time getting scope settings. I just retired yesterday, so hope to have more time to get settings

ashhoe
07-30-2016, 07:00 PM
Hunting season is just around the corner

It's here. It's already getting down to almost 80 degrees at night. Scrapes soon then looking for rub lines.

Moleman-
07-30-2016, 07:57 PM
Hi ashhoe! Met with the farmer last night and signed all the paperwork for the next 12 months so my son and I have a nice quiet spot to hunt. Hope to get in a little squirrel hunting before bow hunting. I was thinking about sending you a pm on Gunco to see if you've got your upper shooting yet.

Hamish
07-30-2016, 08:57 PM
Is anyone else amused at how close this is getting to the .351WSL?

I think this is a very interesting comparison. The .351SL in the M1907 was an evolutionary step up from the M1905 and it's shorter, weaker cartridge. The semi automatic rifle was becoming very popular in the early part of the last century, much the same as the AR now. It may have been a tenth or so longer and the projectile a tiny bit smaller, but this cartridge (that has been kicked around for some years) is a natural evolutionary step in the AR platform, and I fully expect that the more it's done, the more it will catch on.

Personally, I've been considering have a Reamer made for some time to rectify a horrible Contender barrel in .357 Max, but you can bet your bippy I would be all over a AR barrel if the cost came down.

*the portion of the post fuelled by a migraine driven brain fart deleted*

Moleman-
07-30-2016, 09:37 PM
I'd love it if 223 basic were available. There was a article a few years back in one of the gun rags where they went to Hornady. One of the pictures showed a bin of unfinished 223 cases that hadn't been necked down yet. I sent Hornady an email and got a layer type answer about the unfinished cases are unavailable due to liability reasons. A little annoying knowing that I'm straightening back out cases that were straight walled at one point.

Moleman-
06-06-2017, 09:46 AM
A fellow wildcater sent me a few 223 cylindrical cases from Buffalo Arms. They would only need trimmed to length and likely reamed in order to make 357AR 357Max-rimless, or a longer wildcat which is what he is going for. The cases look very good and although they aren't cheap, they would be a real time saver for forming 357AR cases. https://www.buffaloarms.com/223-cylindrical-1-76long-cases-223cyl

Artful
06-06-2017, 12:07 PM
Hmmm, 1.76" long cases - As I recall the longest AR rounds are to be 2.260" - Leaving 0.50" for bullet

Wonder what the RCBS 180grn silhouette leaves sticking out of a case and would it feed?

http://i69.photobucket.com/albums/i80/swedenelson/1111-203-35180GrSILRCBS.jpg

Moleman-
12-19-2017, 03:08 PM
Starline has a limited run of 223 basic brass, $90 for 250 cases. They'd need trimmed and possibly reamed to make 357AR (Max Rimless) which could be done in a single operation with a reamer pilot set up on your trimmer. Not really low on 357AR cases at the moment but I ordered some to test as you can never has too much brass. https://www.starlinebrass.com/whats-...w-products.cfm

woodbutcher
12-22-2017, 01:13 AM
:grin: Hi moleman.Great thread.I`ll saddle up and go along for the ride.
Good luck.Have fun.Be safe.
Leo

just bill
08-28-2018, 09:41 PM
Here are some 357AR (MaxRimless) cases made from 5.56 LC-13 brass and thought I'd show the steps. A couple of guys have made the cases from 357Max brass which just involves changing the rimmed case to rimless, but I like using cheap 223 and 556 brass. So here's the steps:

1. trim to 1.640"-1.650" and debur

2. anneal

3. lube inside the case and expand case mouth with skinny expander

4. expand case body with blunt expander

5. resize

6. roll case shoulder wrinkle away (optional)

7. turn necks/ream to .0105" case wall thickness

8. trim to final length 1.595" and tumble

9. load/shoot


This method seems to work very well as I had no split cases out of the 40 or so I formed in this batch. Hunting season is just around the corner and I figure I'll make another 100 or so since my son is also shooting them now. Usually I've had around 5-10 cases split out of 100 when using once? fired range mystery brass. Any flaw in the case mouth of the parent case will result in a split since they are getting expanded up so much. The initial trim and debur really cuts down on losses. This batch of LC-13 cases probably would of been fine without turning/reaming, but I've had others like FC cases that wouldn't chamber without turning so I just turn them all. Really all you're reaming or turning off is where the base of the bullet would be. The two expander stems are made from a bolt (it's quick and easy) and some hardened drill rod. They just fit into a Lee 38-357 powder through die body

Between 2 forums, and a whole bunch of posts I can recall only one that says step 5 is done with .357 max dies and a.357 taper crimp. There are too many numbers floating around. I suffering from information burn out.
Bill

Moleman-
08-29-2018, 08:26 AM
Any die set that will reload the 357Max will load these. I don't like having to modify die sets if I can help it. The best crimping die that I've found is the 38/357 Lyman taper crimp die as it is actually a gentle taper v/s a modified roll crimp which is very short and does better at crimping into the cannelure that crimping into the smooth bullet side so as to not effect headspace since it headspaces on the case mouth.

The method on the first page of this thread is for modifying 223 cases to straight walled 357AR cases, where as on other sites they mostly talk about converting Starline 223 basic brass. Add in that there is a little bit of technique or finesse involved using different tools and methods and case brands. It's best to do a few cases all the way through to verify your method is producing good cases with your setup than it is to modify everything only to discover they're a little off.

just bill
08-29-2018, 03:08 PM
Any die set that will reload the 357Max will load these. I don't like having to modify die sets if I can help it. The best crimping die that I've found is the 38/357 Lyman taper crimp die as it is actually a gentle taper v/s a modified roll crimp which is very short and does better at crimping into the cannelure that crimping into the smooth bullet side so as to not effect headspace since it headspaces on the case mouth.

The method on the first page of this thread is for modifying 223 cases to straight walled 357AR cases, where as on other sites they mostly talk about converting Starline 223 basic brass. Add in that there is a little bit of technique or finesse involved using different tools and methods and case brands. It's best to do a few cases all the way through to verify your method is producing good cases with your setup than it is to modify everything only to discover they're a little off.

You are so correct, I got bogged down with .308's and 458 socom that some of my equipment accessories for the other calibers disappeared, I'm scratching for basic stuff before I made mods for case trimmers. Even my chop saw needs remodified, due to all the other case trimmer attachments. Even my .22 RCBS pilot's disappeared.

P Flados
12-04-2018, 09:33 PM
As an update, over at MDWS, it looks like they are getting ready to run another batch (round 4) of 357AR barrels.

https://mdws.forumchitchat.com/post/more-blanks-ordered-112618-9930655?pid=1306295022

I have one (not part of a batch) that is currently being made.

In prep for getting the barrel, I had acquired all other parts & pieces, formed a couple hundred brass, cast up a bunch of bullets, made up dummy rounds, etc.

To feed these rounds, removing the side ribs in a Pmag is the most common approach. Last weekend, I did a 20 round Pmag.

One bullet up for magazine testing was the Lee 200 gr. Although I could get them to slide out of the magazine without hangup most of the time, it was pretty obvious that if the round was pushed forward (think gun recoil) the nose of the bullet would drag and hold up as it got pinched between the center rib and the side of the Pmag (see below).

If this happens for a round down in the middle of the stack, the front of the top round is not pushed up and a jam is certain.

231487

Well, I thought I would try my hand at another no lube groove special with a custom "357AR Profile"

First result was 191 gr & real close to 0.358" at the base with a slight taper to 0.355" at the other end of the portion that seats in the case. Meplat is only 50%, but it was the best I could get and "fit" my modified Pmag. As is, I have a "forming die" that will put a perfect edge on the base and "bump up" the body to 0.358"

However, I can also lap the mold to get the boolit OD for the portion in the case more uniform.

Actually the more likely adjustment I will probably do is to make this cavity deeper to get just over 200 gr.

I was pretty happy with the reamer. I got a good harden & temper and it cut decent. I was Ok with the finish inside the mold.

231489

231491

231488

231490

Moleman-
12-04-2018, 10:25 PM
Neat, haven't tried powder coating bullets yet but those seem like they'd feed very well. In a Bulgarian 10rnd mag or thermoold magazine (last resort) the 208gr RCBS/Lee 200gr fit, and will fit in a Pmag if you remove that nub which is a follower stop. The follower will pop up when empty and look odd, but that's about it. Pic doesn't have the cast bullet in it, but shows how the fronts are different on the Bulgarian and thermold as compared to the Pmag. Usually just use one of the bulgarian mags with them.

GARD72977
12-08-2018, 10:30 PM
There is some big news coming soon for this cartridge!

rockrat
12-08-2018, 10:57 PM
So, tell us what is coming soon!!!

Moleman-
12-09-2018, 12:55 AM
I was excited when Starline came out with reasonably priced 223 Basic brass last year, and when MDWS picked up making barrels when I stopped (think they're on their 4th-5th round of them now) there's also a couple other smaller players making barrels who pretty much shadow the latest developments on the MDWS forum and are using my reamer design (357AR or 357AR-2 at Manson Reamers) . It would be nice to have a purpose made mag so guys didn't have to modify them. All ears for what the big news is.

carbine86
12-10-2018, 06:04 AM
Now that is something that I would love to do in an AR, HOWEVER I live in Massa!@#$%^&*()_+_)(*@#^&*&^$#!@^&*(_)(*chusetts and it recently became illegal for me to enjoy my hobby in such a way.
You could swap over a 223 bolt action rifle to it. That could have some really cool potential.