Cmmg Banshee and brass bulges

[phaloxx]

yep just went to evergladesammo.com and ordered 500 of their 165 jhp's for $75 free shipping. Why not? My carry ammo for my pistols is 165gr anyways so it'll get shot either way. I figure keep the same grains of powder "Unique 7.0 grains" for these as what I loaded my 180gr bullets to will increase velocity obviously but not increase pressure, If anything it'll go down a few thousand pounds. Just wonder if changing out the buffer will also help?

[Muskrat]

yep just went to evergladesammo.com and ordered 500 of their 165 jhp's for $75 free shipping. Why not? My carry ammo for my pistols is 165gr anyways so it'll get shot either way. I figure keep the same grains of powder "Unique 7.0 grains" for these as what I loaded my 180gr bullets to will increase velocity obviously but not increase pressure, If anything it'll go down a few thousand pounds. Just wonder if changing out the buffer will also help?

You lost me there. What exactly are you doing?

[phaloxx]

What I meant is ALL my practice ammo is 180gr. So I figure I'd try to move down to 165 gr. Keep the same load data as in powder Unique, AA#9 etc but going from 180gr to 165gr bullets might help alleviate bulging. Just a thought. It may not work but I'm kinda dumb so who knows? I figure less mass moving thru the barrel equals less pressure on the case. It may not work but it's what we all do as reloaders is experiment. That's half the fun. Generally as you go lighter in bullet weights you can increase your powder charge. But I'm going to keep the same powder charge but go to a lighter bullet. See if it helps the bulging/swelling on the brass yet maintain accuracy. If not then I'll back off my powder charge or go to a lighter bullet weight. Not sure yet. Clear as mud now?

[Muskrat]

Ya...makes sense. What you're doing is often cited as a way to turn a USPSA Major load into a USPSA Minor load without having to re-tool the loading press. So under most circumstances it should yield lower pressures and less bulging.

That said, 7 grains of Unique under a 180 grain bullet is a really mellow load. I'd be amazed if you were getting bulging of any consequence with that combo. If you are you might want to look at some other factors...COL maybe?

[Muskrat]

One full week since I e-mailed CMMG and I still haven't heard anything back from them.

Not impressed with their customer service...not at all. You'd think a $1,650 firearm would be better supported by the company.

You guys already solved the mystery for me and I know what they'll say if they ever do respond, but still...

Disappointing. Especially for a US manufacturer selling high-end guns at boutique prices.

[PointBlank82]

I asked them about use of slower powders like AA#9 a couple weeks back and only got radio silence:

Thanks Bryan. Could you ask your engineers if the power factor recommendation is limited to medium speed powders with a sharp pressure/burn curve, or if the use of slower powders such as AA#9 would allow for higher PF without the swelling issue?

I intend to work up a 200 gr XTP load for hog hunting and would prefer to use full power loads for practice. Target velocity would be around 1250 FPS which would put things at 250 PF. With 3.4" of additional barrel, I think I'll be staying below the maximum charge, perhaps keeping pressures below 35k psig. See attached clip from AA manual.


Alternately, I may use an even slower powder such as Lil'Gun which is used in 300 blackout loading for similar effect.

Best Regards,
XXXXXXX

[Muskrat]

CMMG got back to me late today...boiler plate as to what has been posted above.

In a separate email I asked a specific question about recoil buffers and I actually got a specific answer back from a real person...9 days later.

I don't mean to rag on CMMG too hard...I genuinely like the Banshee and I'm glad I bought it. I think they should be more responsive to customer inquiries, but they'll either learn or loose customer base, and that eventually effects them much more than me.

Looks to me like email correspondence is a weak (week?) link with CMMG, and if you want to get any information you should call the sales department (they pick up, Technical Services doesn't) and then ask specific questions that sales can't answer...they'll kick you over to technical services and you've got at least a chance of getting a human being on the phone.

Still very disappointed with CMMG customer service, but I do like the gun.

[BENTENMM]

Sad to hear about the customer service. In building my blowback I got an Angstadt arms bolt from Optics Planet for $92! Holy Hell what an experience that was! I ordered 12/26 and got it 2/14! Several screw ups, all of which were theirs. First and Last time ever doing business with that joke of a retailer. 

On a lighter and much more exciting note.. I just go an SGM 30rd Mag from cheaper than dirt because they had a $10 off coupon last weekend so it was $13.33 delivered.. I have been using ETS mags which have been great so far.. but I feel like just the couple hundred I've put through 2 I've noticed some wear on the all plastic feed lips and wanted to explore my other options for the future...

Since we're on the topic of the Banshee, reloading, and the fact that SGM Mags ship with the Banshee's. I noticed the SGM Mag can fit Loads with a COL of 1.289-1.290"!?!?

Is this the case that others have experienced? My ETS's jam at 1.264ish.. pretty lame. I've only tried 2 of the 6 ETS I have, I'm not sure about the rest. I would assume since ETS is all plastic and SGM is metal lined like a real Glock Mag they're more spacious. Loading out some of the longer bullets would be nice.. I have the Magpul M118LR mags for my AR .308s so I can load out past 2.80" but they only make it in 25rd, kinda odd. DNR asking me why I need a 25rd mag to target shoot..

Thanks for any info on the mags. -Ben

[Muskrat]

Ran a hundred 200 grain BB under 11 grains of AA#9 through the Banshee today.

Got four or five bulges from multi-loaded A-USA brass (garbage brass in my experience), but the rest were fine. I was actually considering culling all my A-USA brass a while ago, but I recon I'll keep using it for target loads and culling it as it bulges in the Banshee.

Some of that brass probably has ten or twelve loads through it, so I'd call it worn brass. Actually glad for the excuse to throw some of it away.

That Banshee rock n' rolls like a vintage jukebox...just damn fun. And accurate. And reliable.

I broke down and ordered the 8oz buffer from CMMG at the ridiculous price of $59. There are cheaper 8oz buffers out there, but they are all too long to work in the Banshee. I might have been able to disassemble and weight the light buffer that came with the gun, but the time and effort didn't seem to justify the savings. Don't need the heavy buffer for my normal shooting loads, but my field loads are Underwood 200 or 220 hard-cast, and I'm not keen to batter my gun for the cost of a dinner and beers at the local brew pub.

Ben: The SMG magazine has proven to be very reliable and of high quality. No idea how it works with long loads, as I just load to book lengths.

[phaloxx]

Ran a hundred 200 grain BB under 11 grains of AA#9 through the Banshee today.

Got four or five bulges from multi-loaded A-USA brass (garbage brass in my experience), but the rest were fine. I was actually considering culling all my A-USA brass a while ago, but I recon I'll keep using it for target loads and culling it as it bulges in the Banshee.

Some of that brass probably has ten or twelve loads through it, so I'd call it worn brass. Actually glad for the excuse to throw some of it away.

That Banshee rock n' rolls like a vintage jukebox...just damn fun. And accurate. And reliable.

I broke down and ordered the 8oz buffer from CMMG at the ridiculous price of $59. There are cheaper 8oz buffers out there, but they are all too long to work in the Banshee. I might have been able to disassemble and weight the light buffer that came with the gun, but the time and effort didn't seem to justify the savings. Don't need the heavy buffer for my normal shooting loads, but my field loads are Underwood 200 or 220 hard-cast, and I'm not keen to batter my gun for the cost of a dinner and beers at the local brew pub.

Ben: The SMG magazine has proven to be very reliable and of high quality. No idea how it works with long loads, as I just load to book lengths.

Check this out! Send that cmmg crap back and get this! Should work in ANY AR style platform!! This is one of the cooler things I've seen in awhile. I know other companies have made similar stuff but not this easy to change out weights or this nice....

https://youtu.be/RbNYm0g77qY

[Muskrat]

That buffer has a maximum weigh of 5.3 ounces, while the heavy Banshee buffer is 8 ounces. The devil's in the details...

[phaloxx]

That buffer has a maximum weigh of 5.3 ounces, while the heavy Banshee buffer is 8 ounces. The devil's in the details...

Damn, well.... so that heavy buffer is supposed to be for high power factors OR if you run suppressed which I never plan on doing. Hmmm I'm wondering if that would alleviate the bulging brass issue. My thought process is with it being forced to push a heavier buffer back that pressure has to go somewhere besides out the barrel and a heavier buffer would actually make brass bulges worse. That's why I'm going down to 165gr bullets. By the way all my Jaggeman brass arrived today. I can tell you this, as I'm running it thru my resizer die before I start loading it up, this stuff is very stout and thick. Working all day in my shop and hopefully can shoot some of this new brass/bullet combo tomm. Will report my findings if I don't blow myself up or catch corona virus between now and then 😉   

[Muskrat]

I don't know if the heavier buffer will affect bulging or not.

It's recommended for loads making 230 PF and above...Underwood, hot Federal offerings, and of course, some reloads.

Loads that make 230 PF are:
165 grains @ 1393 fps
180 grains @ 1277 fps
200 grains @ 1150 fps
220 grains @ 1045 fps

My understanding is that the goal is to increase functional reliability, not to save the brass. I think some of that brass goes in the garbage at the low end, and at the hight end all of it gets thrown away. Underwood 200 grain bullets make 250 PF and the 220 grain bullets make 264 PF, so even with a heavy buffer I don't think the brass is salvageable from the Banshee.

Obviously reduced loads are not going to bulge brass with the regularity of stout offerings, and they even include a reduced weight buffer for people who want to tone it down to .40 S&W levels. I'll be interested to hear what your experiences are with the 165 grain bullets. I shoot a lot of them in my .40 for USPSA, but I haven't loaded any in the 10mm.

[phaloxx]

I don't know if the heavier buffer will affect bulging or not.

It's recommended for loads making 230 PF and above...Underwood, hot Federal offerings, and of course, some reloads.

Loads that make 230 PF are:
165 grains @ 1393 fps
180 grains @ 1277 fps
200 grains @ 1150 fps
220 grains @ 1045 fps

My understanding is that the goal is to increase functional reliability, not to save the brass. I think some of that brass goes in the garbage at the low end, and at the hight end all of it gets thrown away. Underwood 200 grain bullets make 250 PF and the 220 grain bullets make 264 PF, so even with a heavy buffer I don't think the brass is salvageable from the Banshee.

Obviously reduced loads are not going to bulge brass with the regularity of stout offerings, and they even include a reduced weight buffer for people who want to tone it down to .40 S&W levels. I'll be interested to hear what your experiences are with the 165 grain bullets. I shoot a lot of them in my .40 for USPSA, but I haven't loaded any in the 10mm.

Yeah I guess I need to stop thinking about saving brass and focus on fun and reliability. I'll shoot my 1911 more. I know I can save brass from that being fully supported. It's just that damn banshee is sooooo fun to shoot. Oh well. Yeah I'm gonna chronograph these all tomm or Friday but check out jaggeman brass in the meantime. Just from holding it in my hands and looking at this stuff it's friggin stout. It's same price as new starline brass. Wish I had bought some of this sooner cause the case walls and everything are way thicker. Might be able to actually load some nuclear loads with this brass. Later buddy!

[Muskrat]

Ran a few hundred rounds through the Banshee with the 8oz buffer. It definitely slows the carrier down, but everything ran fine...even powder-puff loads (165 grains @ 1200 fps).

No idea how it affects brass bulging. I got a lot of bulging with A-USA brass, but none with S&B brass shooting 200 grains @ 1200 fps.