190 Sub-x Bullet issues

[Bmurph05]

I’ve read about a few people having a similar issue I have been having. Ape_Factory has detailed what seems to be the same issue. The issue is that the bullet will sometimes jam in the feed ramp, and or start to jam in the feed ramp, but get forced past the feed ramp and then jam with the nose of the bullet at the shoulder of the fend ramp, never making it into the chamber.

Ive chased this problem probably way too long, as I’m determined to make this bullet work. Yes, I’m aware of solid copper bullets but am not ready to give up yet. I am scared of a baffle strike with the copper bullets being less stable. I’m at the point where I’m convinced the M4 feed ramps, which were designed to be used with a 556 round, do not work with the combined geometry of the flat nose and wider diameter of the bullet. Seems like the rubber plug of the bullet hits the feed ramp and steep angle, potentially initiating the problem. Or, the wider diameter of the bullet caused the round to be at a steeper angle when feeding, causing the bullet not to feed properly. I think the steep angle may be causing the round to prematurely leave the magazine, and thus jam in the barrel extension.

Here’s, what I’m looking for: for those of you using this bullet without issues (several hundred shots fired without having this issue or any FTF) what specific barrel do you have? I’m ready to take a Dremel to my feed ramp and potentially ruin it in trying to test my theory by taking the feed ramps down. That said, I’d like to buy a replacement barrel that other people have been using successfully as a backup to have on hand.

My upper has the proper feed ramps cut. No lip or overhang. This is the only bullet I have ever had this issue with.

Anderson lower. Wilson Combat 11.3” barrel. Trybe upper. Ive used 300blk pmags as well as lancers 300blk option. Issue is observed with both magazines. COAL has been played with extensively. Better and worse results, but never totally alleviated the problem.

 

[White_Shark]

What OAL are you seating them to?

 

[Bmurph05]

My last notes say 2.04 - 2.08. I’ve gone shorter and longer and didnt record in my notes. Went back to the cannelure and continued troubleshooting. Same issues with varied frequency at all COAL variances. Do you use them without issue? If so, what barrel and lower do you use?

 

[White_Shark]

I load to 2.07 without issue with an FN barrel. What mags are you using? I use Lancer 300 blk mags.

 

[91Eunozs]

Less than 100 or so reloaded rounds, but closer to 500 of the factory sub x rounds through several of my 300 BLK uppers with no issues. All have what I thought were standard M4 feed ramps.

Two with BCM barrels, one Noveske, one DD (I think, might be another BCM), one CMMG, and one Black Hole Weaponry barrel. Don’t recall any feed issues with those rounds, but I tend to load at, or near max OAL.

 

[Ape_Factory]

I never solved the issue in my DI rifles. I tried a wide range of seating depths with no luck. I did theorize that possibly, my BCG, being titanium and thus much lighter than a typical mil-spec BCG/Buffer setup, may be the culprit. I tried different gas settings, springs, even two different barrels, no luck.

I procured a Sig Spear LT in 300 blackout, 9" barrel, and ran factory-loaded rounds, no issues, they all loaded, fired and ejected just fine. So I then tried a few hand loads at a specific head space and seating depth. Success. I then loaded a bunch of rounds, varying headspace and bullet seating depth, threw them in the same magazine, zero FTF's. I basically tried everything within SAMMI specs and they all worked. I could load a 1.069 headspace (on Hornady comparator) all the way up to a 1.078", .002 below chamber length, and all ran fine. Seating depth changes, within reason, didn't matter. Trim length didn't matter. I also switched to the Lee factory crimp dies but normal Redding crimp dies worked too.

I then loaded up a bunch on my Dillon 750, loaded up a 30 round mag to test. Again, zero FTF's. One thing that struck me is the barrel extension on the Sig is quite a bit longer than a typical AR barrel. Behold.

 

[DHDeal]

I load and haven't had any issue with the 190 SubX. I've only loaded it subsonic using H110 and will seat at the bottom of the cannalure. I do load to a specific measurement but don't know the number off of my head and the cannalure just happened to be there. With either a 20 round Magpul or 10 round Lancer magazine they have always fed fine.

Maybe not any help here but when I build these uppers I pay close attention to the barrel extension's sharp edges (the two on the ejection port side that traditionally gouge the shit out of the case necks) and will polish the feed ramps using a cone shaped ultra fine cratex bit and finish polish with a cone shaped felt bit. Regardless of caliber, the case necks don't get the 2 slices in them and the polished feed ramps obviously don't hurt either. I have found the sharp edges I mentioned are there whether it is a Rainier Ultra Match (Craddock chambered Criterion barrel or Shilen), Craddock Bartlein, Proof, Odin works, or Krieger. I just don't like the slices in my case necks but this would have nothing to do with failure to feed issues. The polishing of the feed ramp may however.

My parts list for this rifle that apply to your question:
Iron City Hatchet upper
Ranier Ultra Match 10.3" (I think that's the exact length)
Young Manufacturing NM BCG
Aero Precision M4E1 lower using an Armaspec SRS H1
Magpul or Lancer 300BO magazines
Seating these bullets in Starline brass to the cannalure and using a light crimp using a LEE FCD.

As I stated in the first paragraph, I've never had one round fail to feed (yet) and I'm deep into my 3rd box of 100 190 SubX bullets. Supers (110/115/125's) feed slick also. When I started with the 300BO about 6 months back (until my suppressors arrived I couldn't care less about a 300BO) I read of issues with failure to feed and just never tried anything but specific 300BO magazines because of this. I don't use a progressive press for the 300BO and my dies are Forster and Wilson but I don't see this as part of any problem you are having. I just thought I'd mention it.

I probably misspelled cannelure 6 times in my Post...

 

[db2000]

A1680 and haven’t had any issues except in full auto subsonic. Occasionally jams but didn’t really fool around with the AGB, buffet etc as it was just for fun

 

[Ape_Factory]

Maybe not any help here but when I build these uppers I pay close attention to the barrel extension's sharp edges (the two on the ejection port side that traditionally gouge the shit out of the case necks) and will polish the feed ramps using a cone shaped ultra fine cratex bit and finish polish with a cone shaped felt bit. Regardless of caliber, the case necks don't get the 2 slices in them and the polished feed ramps obviously don't hurt either. I have found the sharp edges I mentioned are there whether it is a Rainier Ultra Match (Craddock chambered Criterion barrel or Shilen), Craddock Bartlein, Proof, Odin works, or Krieger. I just don't like the slices in my case necks but this would have nothing to do with failure to feed issues. The polishing of the feed ramp may however.

You may be on to something with the polishing. I never did that and did have the two "vampire" slices on spent casings. I distinctly remembered seeing them. The bullet itself would look pretty beat up if you chambered it and then ejected the round.

I did try two or three different magazine brands with no change. All of my original testing loads were done on a single stage press with Hornady, Redding, 21st Century, etc...same stuff I'm using on the progressive with the new rounds to feed the Sig. Wasted so many primers!

The barrels I used were Faxon and Rainier Arms, both match grade. VSeven upper. I use the same lightweight bcg components, upper, etc...on my 223 setup and never had any issues with it. Even had a Faxon barrel on the 223 for a bit so likely the angle of feed and the extension itself combined with the Sub-X round and the bullet's shape. All other bullet shapes fed perfectly, from 110 grain all the way up to 220 grain. Zero issues and the gun ran as well (softer shooting to boot) as the Sig does. It was an awesome, lightweight build which came in about 2 pounds less than the Sig!

 

[DHDeal]

It's the ejecting not the feeding that slices the case necks. You may not see it much ejecting a loaded round as the case doesn't smack those 2 lugs on the ejection port side due to the bullet keeping the case away from them (make sense?). A just fired case being ejected under full power is when you see the slices if those 2 lugs are not smoothed up somewhat. Of course, many rounds fired will do the same thing but I like to get ahead of it. I use a fine cratex drum for this.

I'm not trying to bevel those lugs, just smooth them at their tops. I do this for every barrel regardless of who I bought it from. Not being a snob here but if I'm going to do all of the extras building an AR, I'm damn sure going to buy a good barrel. About my starting point is Odin Works but I usually just buy a Proof or a Craddock Precision. I do this work before the barrel ever sees the upper receiver.

As I mentioned in my earlier Post, I have read about some people having issues with this specific bullet but I have not. Maybe it was the Rainier Ultra Match barrel, maybe it was using only 300BO magazines, maybe it is from my polishing of the feed ramps smooth, or maybe I found the perfect seating depth from the start.

 

[Bmurph05]

Less than 100 or so reloaded rounds, but closer to 500 of the factory sub x rounds through several of my 300 BLK uppers with no issues. All have what I thought were standard M4 feed ramps.

Two with BCM barrels, one Noveske, one DD (I think, might be another BCM), one CMMG, and one Black Hole Weaponry barrel. Don’t recall any feed issues with those rounds, but I tend to load at, or near max OAL.

Thanks for sharing. What brand lower do you use? I’m convinced at this point it is a “geometry” issue either due to the barrel extension, where the magazine fits and locks into the lower, or maybe something to do with the upper receiver. My thought right now is to try and modify the barrel extension by taking some of the angle out of the feed ramps. But I’m also going to try to take a close look at a few of my friends AR’s and see if I can find any other sort of difference in spec between those things.

 

[Bmurph05]

I never solved the issue in my DI rifles. I tried a wide range of seating depths with no luck. I did theorize that possibly, my BCG, being titanium and thus much lighter than a typical mil-spec BCG/Buffer setup, may be the culprit. I tried different gas settings, springs, even two different barrels, no luck.

I procured a Sig Spear LT in 300 blackout, 9" barrel, and ran factory-loaded rounds, no issues, they all loaded, fired and ejected just fine. So I then tried a few hand loads at a specific head space and seating depth. Success. I then loaded a bunch of rounds, varying headspace and bullet seating depth, threw them in the same magazine, zero FTF's. I basically tried everything within SAMMI specs and they all worked. I could load a 1.069 headspace (on Hornady comparator) all the way up to a 1.078", .002 below chamber length, and all ran fine. Seating depth changes, within reason, didn't matter. Trim length didn't matter. I also switched to the Lee factory crimp dies but normal Redding crimp dies worked too.

I then loaded up a bunch on my Dillon 750, loaded up a 30 round mag to test. Again, zero FTF's. One thing that struck me is the barrel extension on the Sig is quite a bit longer than a typical AR barrel. Behold.

Wow, that barrel extension certainly looks different. Great info. If I cant make mine work, I’m going to take a stab at buying something one of you guys say is working. So, all of this info is exactly what I was looking for. Thanks!

 

[Ape_Factory]

Wow, that barrel extension certainly looks different. Great info. If I cant make mine work, I’m going to take a stab at buying something one of you guys say is working. So, all of this info is exactly what I was looking for. Thanks!

If at first you don't succeed, throw money at it! I probably should have worked with my setup more but I got the "piston" bug and thought why not. Plus the Sig folds up nice and small.

On the DI guns, I was using ADM lowers. It's gotta be a feed ramp issue. Just finished loading a big batch of the 190's over the weekend.

 

[Bmurph05]

I load and haven't had any issue with the 190 SubX. I've only loaded it subsonic using H110 and will seat at the bottom of the cannalure. I do load to a specific measurement but don't know the number off of my head and the cannalure just happened to be there. With either a 20 round Magpul or 10 round Lancer magazine they have always fed fine.

Maybe not any help here but when I build these uppers I pay close attention to the barrel extension's sharp edges (the two on the ejection port side that traditionally gouge the shit out of the case necks) and will polish the feed ramps using a cone shaped ultra fine cratex bit and finish polish with a cone shaped felt bit. Regardless of caliber, the case necks don't get the 2 slices in them and the polished feed ramps obviously don't hurt either. I have found the sharp edges I mentioned are there whether it is a Rainier Ultra Match (Craddock chambered Criterion barrel or Shilen), Craddock Bartlein, Proof, Odin works, or Krieger. I just don't like the slices in my case necks but this would have nothing to do with failure to feed issues. The polishing of the feed ramp may however.

My parts list for this rifle that apply to your question:
Iron City Hatchet upper
Ranier Ultra Match 10.3" (I think that's the exact length)
Young Manufacturing NM BCG
Aero Precision M4E1 lower using an Armaspec SRS H1
Magpul or Lancer 300BO magazines
Seating these bullets in Starline brass to the cannalure and using a light crimp using a LEE FCD.

As I stated in the first paragraph, I've never had one round fail to feed (yet) and I'm deep into my 3rd box of 100 190 SubX bullets. Supers (110/115/125's) feed slick also. When I started with the 300BO about 6 months back (until my suppressors arrived I couldn't care less about a 300BO) I read of issues with failure to feed and just never tried anything but specific 300BO magazines because of this. I don't use a progressive press for the 300BO and my dies are Forster and Wilson but I don't see this as part of any problem you are having. I just thought I'd mention it.

I probably misspelled cannelure 6 times in my Post...

I greatly appreciate the details.

Polishing the feed ramps is what I have done so far. The Wilson Combat barrel comes polished already, but I bought some off brand Kratex type bits and started by polishing the ramps. I did it once, and it seemed like I had less FTF’s, but still they remained. So I went at it a bit more. This time I thought I had resolved the problem. I did a little more than polishing; I took out the sharp edges and gently tried to work the angle down a bit. Another 90 rounds without FTF. I thought I fixed it. But then it happened again. And then it go to where I had it happen multiple times on a magazine again (I think once the ramps get dirty it causes that rubber flat tip to stick in the ramps rather than slide through, but I certainly am not sure of this. Just a theory). So here I am.

I contacted Wilson Combat as well as Hornady about this. Both said they weren’t aware of an issue like this. In asking specific questions about the feed ramp, they simply said this their design was proprietary and that I could send it in if I wanted. Hornady said play with the COL and then just said the bullet may not work with my set up.…They’re has to be a reason.

 

[Bmurph05]

If at first you don't succeed, throw money at it! I probably should have worked with my setup more but I got the "piston" bug and thought why not. Plus the Sig folds up nice and small.

On the DI guns, I was using ADM lowers. It's gotta be a feed ramp issue. Just finished loading a big batch of the 190's over the weekend.

Ha! I agree. Hopefully I can just buy a new barrel and be done. Gotta make this work. HD tool.

 

[Bmurph05]

It's the ejecting not the feeding that slices the case necks. You may not see it much ejecting a loaded round as the case doesn't smack those 2 lugs on the ejection port side due to the bullet keeping the case away from them (make sense?). A just fired case being ejected under full power is when you see the slices if those 2 lugs are not smoothed up somewhat. Of course, many rounds fired will do the same thing but I like to get ahead of it. I use a fine cratex drum for this.

I'm not trying to bevel those lugs, just smooth them at their tops. I do this for every barrel regardless of who I bought it from. Not being a snob here but if I'm going to do all of the extras building an AR, I'm damn sure going to buy a good barrel. About my starting point is Odin Works but I usually just buy a Proof or a Craddock Precision. I do this work before the barrel ever sees the upper receiver.

As I mentioned in my earlier Post, I have read about some people having issues with this specific bullet but I have not. Maybe it was the Rainier Ultra Match barrel, maybe it was using only 300BO magazines, maybe it is from my polishing of the feed ramps smooth, or maybe I found the perfect seating depth from the start.

I’ve gone all over the place with seating depth. I’m fully convinced that isnt the issue. I’m also using 300 BLK magazines, so cross that off the list as well. Hopefully just needs a different barrel.

Bolt comes forward, grabs bullet. Bullet is pushed forward. Bullet contacts feed ramp. Continues forward and is guided into the chamber, and some point is leaves the magazine in between. Considering all of this, Different specs in the upper, lower or barrel extension have to be the problem. If the dimensions are different anywhere between those things, I can see how it could affect the round feeding from magazine to chamber. Been hoping someone else has wrestled this problem to the ground but here we are! If I swap barrels soon I’ll update with results.

 

[91Eunozs]

Thanks for sharing. What brand lower do you use? I’m convinced at this point it is a “geometry” issue either due to the barrel extension, where the magazine fits and locks into the lower, or maybe something to do with the upper receiver. My thought right now is to try and modify the barrel extension by taking some of the angle out of the feed ramps. But I’m also going to try to take a close look at a few of my friends AR’s and see if I can find any other sort of difference in spec between those things.

Several, but most are Aero Precision or Quentin Defense. One is an Umbrella Corp Weapons Research Group lower.

The Quentin Defense lowers always have matching Quentin Defense uppers, but the Aero lowers have a mix of Aero, BCM, or whatever upper receiver PSA happened to have on sale when I was building that upper…hell, I think there’s even one lowly Anderson upper receiver in the mix somewhere I think. Pretty sure that’s the one with the CMMG barrel.

 

[DHDeal]

I definitely appreciate your "gonna figure this out" attitude. Going back to your pictures, you are running a shorter OAL than I but not that much. It is definitely jamming the rounds at a steep angle. I didn't read if you have tried a different BCG (or just another bolt) but you probably have.

Not that you asked me specifically but my lower is a Areo M4E1, a Armaspec SRS w/H1 weight, and a Triggertech Adaptable trigger.

 

[Bmurph05]

I definitely appreciate your "gonna figure this out" attitude. Going back to your pictures, you are running a shorter OAL than I but not that much. It is definitely jamming the rounds at a steep angle. I didn't read if you have tried a different BCG (or just another bolt) but you probably have.

Not that you asked me specifically but my lower is a Areo M4E1, a Armaspec SRS w/H1 weight, and a Triggertech Adaptable trigger.

I have tried another BCG. I appreciate the other info.

Ive got a Rainier Arms barrel on order. Once it gets here I’m going to further evaluate.

 

[Jordanledwards1]

Any updates? I’ve had some issues with my dd pdw doing the same.

 

[Bmurph05]

Any updates? I’ve had some issues with my dd pdw doing the same.

I did recently get the Rainier Arms barrel. I haven’t fully tested it out, but here’s what I have so far:

I manually cycled 480 rounds through. Zero FTF’s. This was not the case previously. I could manually induce the FTF with the other barrel.

I visually compared the two feed ramps. I was happy to see some minor differences. It does appear that the feed ramps in the Rainier barrel are very slightly wider. The notch between the two feed ramps has less of a profile on the Rainier. The Rainier barrel a “thinner gauge” or less thickness for the outside wall of the extension.

This is all very unscientific. I’m just some asshole. That said, I think the key takeaway from the feed ramp differences are that there is in fact some differences. We do have different geometry for the bullet as it is pushed through the extension. This is what I was hoping for, since I’m convinced/hoping that simply a different barrel extension would solve the problem. I believe that the nose of the bullet is “catching” in the feed ramp, disrupting the feed cycle. I‘ve got a little more evidence of this, but I will explain in another post more thoroughly. That said, I haven’t proved my theory as to why I think this problem was occurring yet. But, I am more convinced that I am correct.

I’ve got to shoot a few hundred rounds without any FTF before I’ll be confident. None of the suppliers that I checked have any in stock right now. I only have less than 200. Today, I will likely run some through to see how they do, but I wont be able to really do what I want until I can buy more bullets. Boy, this cheaper bullet option really is saving me some money! (money isn't the only reason I want this to work, but it is one)

I’m going to attach the photo. It’s not a great photo, but its the best one my IPhone 6 took. You have to look close to see the differences, but they are there. Wilson Combat barrel on right, Rainier on left. Keep in mind That I have worked the WC barrel with some polishing bits and a dremel. I did take some small amounts of metal out of the WC feed ramps already. So this isnt a true representation of a factory WC barrel extension anymore.