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Mr Humble
08-20-2016, 10:28 PM
This is my second one. Bushmaster upper on a Remington (Bushmaster) lower. 1.5-6 Leupold. Shoots Hornady factory (jacketed) so good it's scary. 3 frequently a clover leaf @100.

No shortage of .452 cast boolits. Have a Lee 300 gr GC semi wadcutter that is deadly in my 1926 Colt New Service Match Target. So I dug out my stash of Bushmaster loading data. In-terp-polated and tried H110 and 4227. Not enough H110 to fully cycle, 4227 worked but there are feeding issues.

Neither shot what could be called "groups".

This was my result with H110 .... not too bad you say ..... it was shot a FIFTY FEET ! (12 shots)

At 50 yards is was a joke but the semi wadcutters are cutting clean holes, no tipping.

Twist is 1 in 16 and some claim its a gain twist.

Thoughts ? Suggestions ? Thanks !

174873

Yodogsandman
08-21-2016, 07:47 AM
Work out your feed issues and it will probably come around. Check seating depths and crimp amounts.

Mr Humble
08-21-2016, 12:44 PM
450 BM uses a tapered crimp and is set correctly.

Gonna seat em' in farther as semi wadcutters never are great semi auto feeders. Also gonna try some lighter/shorter boolits as Hornady slugs are quite short. 200 gr truncated cone .452s might be better.

rockrat
08-21-2016, 05:48 PM
I use Lil Gun in mine with the Lee boolit sized .454". 2" and less @100.

Mr Humble
08-21-2016, 08:35 PM
Today I tried 200 gr truncated cone wadcutters w/37 gr of 4427 and CCI SR magnums.
Out of 10, I had 4 bloopers and six all over the place. Have to recheck my dies as the taper crimp on this cartridge is very critical.

Mr Humble
08-22-2016, 12:13 AM
I use Lil Gun in mine with the Lee boolit sized .454". 2" and less @100.

Charge ? primer ? which Lee ? OAL ? taper crimp diameter @ mouth ? Thanks

Whiterabbit
08-22-2016, 12:38 AM
I've shot a 460 S&W with a 1 in 16 twist with what seems like every cast bullet under the sun minus a 200 grain GC (call me if you have some) with H110.

Anyways, I have had similar results to you, in similar conditions. I suggest you up the bullet weight to over 400. Try some 45/70 bullets in the 400-540 grain weight. 400-450 with gas check. Above 450, no need. Still with H110, even up to and above 540 grains. Make sure the bullet selection has LOTS of driving band. Lots, and lots, and lots.

I think you'll fine something accurate much more easy.

And if not, my second suggestion is to reset with the 300 grain bullet that feeds, and try a new powder. H4198 or similar. something slightly slower than H110, a fast rifle powder. Something on the very fast side for 223, even just too fast. That range.

Mr Humble
08-22-2016, 12:00 PM
Thanks. I have the 300 gr Lee 452 300 RF GC that I'll try with 4198. 450 Bm loading data is scant but the 460 S&W data is close. As loads for 4227, Lil Gun and H110 are available for both, some caution interpolation should provide a start for 4198.

I also have tapered crimp diameter issues (very impt in BM) to correct. First I have to blast out all that unburned 4227 out of the gun.

Mr Humble
08-27-2016, 08:48 PM
Got the crimp issue fixed, no missfires.

Tried the 300 Lee GC again with powder coating.

Tried 4227 again and 4198.

Groups @50 still 5" with no evidence of tipping.

The same bullet shoots very well in both 45 Colt and 460 S&W.

I'm gobsmacked !

Yodogsandman
08-28-2016, 11:52 AM
Are you using gas checks?

Have you fired a round and then checked for nose damage on the next round by hand ejecting it?

Try different seating depths. Roll loaded rounds on a flat surface to see if they're seating straight.

Powder coated boolits have consistency problems due to the uneven surface coating. Powder coated boolits are not as accurate as lubed ones. Any decent lube should work well.

Mr Humble
08-28-2016, 09:43 PM
are you using gas checks? Yes

have you fired a round and then checked for nose damage on the next round by hand ejecting it? All are single loaded

try different seating depths. Roll loaded rounds on a flat surface to see if they're seating straight. Seating depth is pretty much fixed to get feeding. They are straight. The hornady dies are a 4 die set .... #4 aligns and taper crimps

powder coated boolits have consistency problems due to the uneven surface coating. Powder coated boolits are not as accurate as lubed ones. Any decent lube should work well. found some groups i shot in my first 450. Used lil gun and lubed boolits. About 2" @50 yards.

Where does "powder coated not as accurate" come from ?
Have there been side x side tests published here ?

Thanks.

Yodogsandman
08-29-2016, 02:24 PM
"powder coated not as accurate"

You can quote me for that statement, my personal testing proves it in my rifles. I have not shot PC in any pistol, I lube those with BLL.

Have there been side x side tests published here ?

Not that I've seen. Most using PC in rifles say that they get great accuracy but, don't post the results. Look in the PC sub forum for any posted results.

http://castboolits.gunloads.com/showthread.php?220557-Real-Accuracy-(2-moa-or-less)-with-Coated-Rifle-Bullets-at-1800-fps-or-greater

Whiterabbit
08-29-2016, 03:12 PM
Got the crimp issue fixed, no missfires.

Tried the 300 Lee GC again with powder coating.

Tried 4227 again and 4198.

Groups @50 still 5" with no evidence of tipping.

The same bullet shoots very well in both 45 Colt and 460 S&W.

I'm gobsmacked !

Get someone to send you some 405 grain 45/70 bullets, and put then through the .452 sizer. Give them 32 grains of H4198 and tell me how that works for you.

Note: I have no idea what the pressure is for that load, but it's WELL under the 65ksi ceiling for 460 S&W so I'm making an educated guess that it's near 50ksi for an AR-15, but I have no idea, and it's not my cheek on the thing when the trigger is pulled. I can also say that the load can tolerate going way down in powder, 29, 28 grains, so you can work up if you want. But should find a node in the 31.4-32 grain area.

Mr Humble
08-30-2016, 02:27 PM
Have some 330 RN 45-70 boolits, sized em' to .452. Trying Lil Gun as it was the best with my previous 450BM with the 300 gr .452 Lee GC boolit.

If that fails, I'll try 4198 again.

Thanks !

Whiterabbit
08-30-2016, 04:33 PM
OK, but keep in mind my #1 purpose was to get you trying heavier (longer) bullets, particularly if they are plain base. My personal advice wouldn't change if you reported no success with the 330's.

Gtek
08-30-2016, 06:34 PM
Bushmaster factory upper, 1-16" ?

jcren
08-30-2016, 07:40 PM
Check with Smoke4320. He sells pc and has posted many targets showing it can be done. I believe one of his rifles is a big bore ar, but details escape me.

Mr Humble
09-03-2016, 11:13 AM
Yes it's a Bushmaster upper on a Remington (Bushmaster) R15 lower.

rockrat
09-03-2016, 06:53 PM
Sorry, Lee 300gr mould for the long colt. rifle gas checks. .454"dia. Rem 7 1/2 primer. 32gr Lil Gun. (works in MY gun, the way I load it--use at your own risk). I taper crimp using a 284 win. sizing die.

Mr Humble
09-04-2016, 12:18 PM
RR, thanks, there is only one Lee mold that is a .452 300 gr GC. (45colt/454casull), that's the one I have. I have been PCing it and running it thru a .452 Lee die. I'll try it w/o sizing which should put at @.454.

In the past when using it with SPG, no leading but 4-5" groups @50.

First I have to try the resized 45-70 boolist suggested by WhiteRabbit.

I have the Hornady 4 die 450BM set that works perfectly when you taper crimp ONLY and not less than .474.

Mr Humble
09-06-2016, 09:37 PM
Well the beat goes on. As suggested, I tried some 300 gr 45-70 boolits sized to .452. 5 in 6" @ 50. Just got in a box of commercial 350 gr .458s that are "gascheckable". There next on the list.
Gonna cast up some the Lee 300 GC ones, size em' to .452 and PC them. MTF.

Whiterabbit
09-07-2016, 12:17 AM
As suggested, did you try something well over 400 grains? That was the key. Lots of length, lots of driving band.

If you want a cheap 500 to play with, lee makes one that *should* fit a 450BM with OAL limitations.

http://www.midwayusa.com/product/489225/lee-2-cavity-bullet-mold-c457-500-f-45-70-government-457-diameter-500-grain-flat-nose-gas-check

The gas check can only help. @ $20 worth trying too. If some 405's or 450's don't work.

Whiterabbit
09-07-2016, 01:27 AM
Here's the BEST bullet I have found so far for a 2.3" OAL .452 cartridge with a long-ish (10" for me) 16 twist barrel.

460-425 RD. Even came in a 6 cav mold. Today it comes in a 5 cav with std lube grooves from NOE for a steal of a price for bullet performance. I can get the same performance from a 500 PB but longer than 2.3" OAL.

The secret sauce IMO is the insane bearing surface yielding supreme stability in the rifling. Cast in hardball the expansion is weak but the penetration is absurd. 32 grains of 4198 yields 1430 fps in my 10" barrel. a 500 PB with 31 grains only gives up 60 fps and is much more likely to expand given a more tipped nose.

I have tried every bullet under the sun from 200-730 grains. The only bullet I have not tried is is 250gr and under gas checked bullet. Under 240 grains I have used thick-jacketed and the barnes solid.

The best bullet at high pressure with the 16 inch twist barrel was by far the 425 RD, followed by the 500PB in a BPCR flavor profile, closely followed by the 200 grain barnes (needs H110), followed by the 290 grain barnes (also H110, you would not believe the mushroom on the 290 grain TEZ at 2000 fps). For me, that's plenty of choice. after this, it's 370 grain class bullets, more hard ball driven fast. After that, 550-600 grain bullets, but why? that's (for you) near a pound of lead per magazine.

I have not had luck with 300-350 grain bullets, whether LEE, Penn with the silver alloy, or generic plain based 300 grain hardball. H110, AA#9, 4198, 4759. I won't bother trying longshot. Why? The secret sauce is in well over 400 grains. I really, really, really want 300 LEE to work. I could MASS cast one bullet for 45 colt and 460s. I just couldn't get it to work.

I am NOT surprised to see your struggle. Maybe someone else figured out the secret to getting the 300 grain class bullets to work. I have shot thousands (in total, many hundreds of 300's), and I couldn't make it work. Too many smarter people than me , I know it can work. But why bother? You have 4198, so get you some 400+ and load up the Hammer of God and destroy some frameworks holding up the steel plates. The steel loves slow moving cast, but it's murder on the frames. That is somehow satisfying to me.

Mr Humble
09-07-2016, 01:00 PM
WR THANKS!!!! I'll order the mold today.

Now questions:

1. what do you size it to ?

2. with that bullet and 32 gr 4198, did you have to change the buffer spring from the stock 223 one ?

3. have you tried powder coating this boolit ?

Thanks again !

Whiterabbit
09-07-2016, 02:45 PM
I shoot these via revolver, so no need to worry about buffer. Only whether I am under a 65ksi pressure ceiling. 10" barrel, 1 in 16 twist. (this is post #7)

Size to .4525-ish via .452 die polished ever so slightly (aka useless and un-needed gesture)

I'm trying to touch bullets less, not more. powder coating as far as I can see at this time not only requires an additional step for processing, but requires touching every single bullet to load in specific ways for bake-out. That's not something I am interested in when I can pop them into and out of a lyman45, and could consider getting a star for even faster performance. If I could do it shake and bake style on a tray that would self-align bullets when going into the heat treat furnace, I could see going to PC. But for now, I use std lubes and processing.

odfairfaxsub
09-07-2016, 02:51 PM
"powder coated not as accurate"

You can quote me for that statement, my personal testing proves it in my rifles. I have not shot PC in any pistol, I lube those with BLL.

Have there been side x side tests published here ?

Not that I've seen. Most using PC in rifles say that they get great accuracy but, don't post the results. Look in the PC sub forum for any posted results.

http://castboolits.gunloads.com/showthread.php?220557-Real-Accuracy-(2-moa-or-less)-with-Coated-Rifle-Bullets-at-1800-fps-or-greater


Not to turn this forum thread on a heel but my pistols seem to shoot better as lubed and not powder coated. Well what normally would be 2 inches w lubed would be 2 1/2 inches in powder coat. Now my rifle in 300 AAC shoots soooooo well in powder coat. I think gun may depend on one way or another

Yodogsandman
09-07-2016, 03:56 PM
Not to turn this forum thread on a heel but my pistols seem to shoot better as lubed and not powder coated. Well what normally would be 2 inches w lubed would be 2 1/2 inches in powder coat. Now my rifle in 300 AAC shoots soooooo well in powder coat. I think gun may depend on one way or another

Depends on velocities, really. Boolits shot at rifle velocities aren't accurate for most. Let's say >1800 FPS for a rifle. Would you mind posting your velocity and group at "X" far away for your gun? I just need to be edumacated. I'd love to shoot PC better than lube in a rifle.

Mr Humble
09-07-2016, 07:46 PM
The mold was in stock at NOE (2 cav) and also ordered the SAECO nose punch. I have SAECO .452 and .454 dies.

Also found a boolit quite like the NOE (Cast Performance Bullets 45 Caliber (459 Diameter) 420 Grain Lead Flat Nose Gas Check) so I ordered 50 to try.

As for touching boolits to PC them, I wear Nitrile gloves, so they never are touched until after PCed. Cast lubed boolits are handled going into the sizer, coming out, seated and probably during inspection and shooting. Lead transfer in handling is only a concern if you don't wash your hands well. Fume inhalation while casting is far more dangerous.

But, I also drink coffee w/Brandy, have a beer and a glass of red wine everyday. Started casting at 15 and 60 years later my lead levels are just fine.

Whiterabbit
09-08-2016, 01:18 AM
no, by touch, I mean throughput concerns with respect to methods of manufacturing. For example, I don't have to touch every piece of brass anymore since I have a sifter for removing tumbler media, progressive press with case feeder, etc. I don't have to touch every primer because my priming setup doesn't use tubes, but the shake and cover system. I still have to touch every bullet because I haven't found a good bullet collator yet. And that definitely holds true for casting since I lube via lyman 45. That just takes time, there's no way around it. Tumble lubing is no good for my needs. If I can batch process PC material without having to touch every bullet (auto collating via shake table, or whatever it would take), then I have a compelling reason to manufacture via that method.

Today I "touch" every (cast lead) bullet by hand, sometimes with nitrile and sometimes bare hands. My lead levels at last check were about 50% the national limit for the lowest level of concern. In other words, not even close to a concern.

Anyways, which mold did you buy, the PB or GC version? I've been eyeballing a 5 cav PB to compliment my 6 cav GC from ranch dog.

Mr Humble
09-08-2016, 10:50 AM
Gas check as the other potential uses (45-70, 458 WM) require them.

Whiterabbit
09-08-2016, 11:40 AM
if it doesn't work for the BM (and I am betting it does), your 45/70 will love​ that bullet. I bet the winmag would like it too.

Third warning, I have no idea what pressure 32 grains of H4198 runs, but my revolver is good to 65ksi. My understanding is AR15's are good to 50 ksi. I know I am well under 65ksi but might be above 50, I have no idea. Fortunately, 4198 has been very forgiving to me (I am using LRM primers) and you can really download if you prefer to work up with caution.

odfairfaxsub
09-08-2016, 02:29 PM
Depends on velocities, really. Boolits shot at rifle velocities aren't accurate for most. Let's say >1800 FPS for a rifle. Would you mind posting your velocity and group at "X" far away for your gun? I just need to be edumacated. I'd love to shoot PC better than lube in a rifle.


My aac load was just shy being under the sound barrier. My group was 5 shots in what appeared to be a 45 cal bullet hole around 50 yards. Used a t-1 aimpoint. I'm going to put a actual scope on this gun and milk my load for all its potential

Oklahoma Rebel
09-09-2016, 02:08 PM
I always thought those were .458 just like 460 S&W

Mr Humble
09-09-2016, 08:59 PM
Nope both the 450 BM and the 460 S&W are .452.

Mr Humble
09-17-2016, 11:00 PM
WR, gets the gold star. I resized some of the commercial 45-70 430s from MW to .454 and loaded them over 25 gr of 4227 with std WSR primers. This load seals well, no smoky cases and functions fine. There is so much debate about acceptable pressures all over the net. The barrel has the same chamber thickness as a 284 Win bolt gun that runs at 60K but Hornady factory loads are
<40K. I find it hard to believe that the BM action/barrel is not as strong as a 460 S&W revolver.

The 460 will push a 395 gr boolit at 1800 w/56K pressure in a 10" bbl. Going to stick my new chronograph on it and see if 1500 is obtainable with the 430 with acceptable pressure.

Results @50 with the 25 gr load:

176864

Whiterabbit
09-18-2016, 12:33 AM
And that's your first pass? ten bucks says you get it shooting (on a good day) an inch at 100 without too much fuss. Just need to optimize bullet weight/length/design, and develop the right amount of 4227.

Sounds like the home stretch now.

Whiterabbit
09-18-2016, 12:35 AM
I always heard that it was the bolt that was weak on an AR, not the chamber. That, for example, a case with a large head like 7.62x39 tended to shear lugs on the bolt.

Moleman-
09-18-2016, 10:49 AM
That and the chambers getting a ring at the minor diameter relief cut just behind the barrel extension. I always wonder if the pics you find online are from guys trying to hot rod the cartridge though.

Digital Dan
09-18-2016, 11:18 AM
Couple of stray thoughts:

Have you slugged your barrel? SAAMI bore specs are .450" groove/.422 bore.

What alloy are you using?

Mr Humble
09-18-2016, 12:20 PM
1. OK, typically boolits are 3 thou over as in .311 in 30-06. All 450 BM jacketed bullets are .452, so .454 is a minor squeeze. The clean fired cases show the obduration is excellent, which is not true using .452 boolits.

2. The alloy is whatever the company that makes the boolits uses. When I use my new NOE mold it will be wheelweight.

Shearing bolt heads ? Never seen one. Were the loads tested or is this more internet "facts" ? Could not find a single incident of a 450BM sheared bolt. Most experts believe that a big fat straight case grips the chamber walls better, than a bottle neck one, given equal chamber pressure. The failure of the 22 Jet in S&W revolvers is a perfect example. 460 BM in a revolver has no problems running loads at the same pressure.

Bulged chambers ? Same question. From Gun Digest:

"Bullet Ballistics: Peak Pressure

A few things to note: First, peak pressure comes when the bullet has moved only about 3 inches, even with the slow-burning fuels appropriate for a .300 magnum. Pressure drops off fast, too, losing 90 percent of its vigor in the next 18 inches of barrel. But the bullet continues to accelerate even as pressure behind it diminishes. Between 14 and 21 inches, pressure loss totals 18,000 psi."

So, the barrel should be bulged, NOT the chamber. More internet "facts".

Whiterabbit
09-18-2016, 06:56 PM
No worries. I was not, even for a moment, questioning the work you've done or the strength of your gun or any. As you say, internet facts. If yours or my load is 90ksi, and we shoot 1000 of them with no issue, who's to say there's a problem.

I think the benchresters do this regularly, in fact. Or maybe just to 500 rounds then spin a new barrel on :)

Mr Humble
09-18-2016, 11:13 PM
WR, up to the range today with


https://media.midwayusa.com/productimages/252x189/primary/977/977389.jpg (https://www.midwayusa.com/product/977389/oregon-trail-trueshot-cast-bullets-45-caliber-459-diameter-430-grain-lead-flat-nose-gas-check-box-of-50)Oregon Trail Trueshot Cast Bullets 45 Caliber (459 Diameter) 430 Gr.. (https://www.midwayusa.com/product/977389/oregon-trail-trueshot-cast-bullets-45-caliber-459-diameter-430-grain-lead-flat-nose-gas-check-box-of-50)


Resized to .454.

My previous load of 25 gr at 50 yds was posted previously.
Today I tries 27,29 & 31 gr of 4227 at 100. 3 shot groups came in at 1.5" wide but 3.5" high.

These loads showed no real difference in obvious pressure signs. Cases were not damaged and primers (CCI SR Mag) all looked the same.

These boolits don't cut real clean holes, so it's hard to tell if any tipping is present.

WR... suggestions ?

Whiterabbit
09-19-2016, 01:35 AM
Just a couple.

First, if you question tipping, they aren't. These are huge bullets, you'll see a nice nose profile and a bullet hole as long s the bullet. They are spinning like crazy when the tumble. Like the 740 grain bullets I tried. Most cut a nice clean hole, then one of them.....

http://castboolits.gunloads.com/attachment.php?attachmentid=158029&d=1452709049

Anyway, IMO looks like you got a great bullet. Maybe try a different powder? That was also key for me. Though I have to admit, for me a powder either worked in some way, or I got results like you see above with tumbling (at any distance). I might also check a chrono or consider lock time, one powder choice for me tended to result in hang fires which of course affect all sorts of performance.

Seems to me you are close though. Better than the old performance, at triple the distance. So you're getting part of the magic, just gotta figure out what you are doing right and keep going farther. Use H110? 4759? IMR4198? AA#9? try a 500 grain 457-500-F LEE bullet? Cast your own so you can swap out lube? (alox doesnt work for me)

If none of these work for you, I'm out of experience. Maybe a different powder still. 4895? that powder is a failure for me, but your gun is basically a baby 45/70. Consider treating it like one, rather than a hyper pistol cartridge.

Mr Humble
09-19-2016, 05:32 PM
Thanks, I cast up a bunch today from the new NOE mold. Still chasing speed goats but I'll get to gas checking/PCing and sizing them soon.

According to Hodgdon, in the 460 S&W, (probably the best surrogate for the 450BM), with a 395 cast boolit, the powder choices are Lil Gun, 4227, 4198 & H110.

Think I'll start with 4198.

More to follow, Thanks!

Whiterabbit
09-19-2016, 07:57 PM
wow! Hodgdon did not have 4198 data before. New! cool. 38 grains for 395 at 46ksi, I'm way underpowered with 32 grains in my 425's! Maybe I should cram a ton more powder in there and see where that gets me ;) (kidding)

Mr Humble
10-13-2016, 12:28 PM
WR, I tried 27 gr (guesstimating from 460 S&W data) with that NOE ton'o lead bullet. At 50 I got a 5 shot group that was .75" wide and 5" high. A friend who is a big cast boolit shooter says to switch from SR magnum primers to regulars.

You have any thoughts ? Thanks!

Whiterabbit
10-13-2016, 03:19 PM
I have no data, only opinions. I exhausted any data based reasoning I had already. Sorry. But I have opinions!

That's the "44man" method of thinking. Keep going down that path, why not small pistol? Find the weakest primer you can.

I use Winchester LRM's which have to be the least enthusiasm-generating primer out there, because they seem like the universally un-favorite primer.

My real opinion is, try the 44man method. It'll cost you $12 at your LGS to get a few primer types from SR to SP, see if you get any improvement. Why not? Maybe your 45 bush will do better with the weakest primer.

Mr Humble
10-14-2016, 08:39 PM
I have em' all. First trying reg SR. Thanks!

Mr Humble
12-09-2016, 12:56 PM
Putting it away for the winter. My new Tikka T3 308 w/threaded muzzle for can just showed up. Put my 4-16x50 S&B on it and see what it will do.

182349

TMenezes
12-09-2016, 06:52 PM
I use Accurate 1680 for my 458 Socom, so I checked what they had for 450 BM. They list this,

300 HDY XTP 37.5 1,741 41.7 1,900 39,260 2.085

I know this is for a jacketed slug but it gives you something to go on. 1680 is kind of an oddball powder but works fantastic in very specific applications like this.