9x25 DI AR

[mrpipesmkr]

  I finally bit the bullet and with the help 0f Ron Williams of RMW Xtreme built an AR in a caliber I have long felt would make an excellent carbine.  I am attaching pictures of my latest AR chambered in 9x25 Dillon. Ron supplied the upper and I built a Large Glock Quarter Circle 10 lower for the project.
   I have to say that Ron has really made the difference in developing this piece for me and making it run. He is the "go to guy" for D.I. pistol caliber uppers for the AR!  Not only did he locate a 9x25 Dillon ream to use, he designed the gas system to function at the 9x25 pressures. Getting the 9x25 ream was important for me as I wanted a carbine that would have common magazines and ammunition with my G20.  As is to be expected with a project like this there was some "dialing in" to do with the gun initially?   I at first had some failure to feeds and jams, about 6-7 out of the first 50 rounds.  Ron spent a lot of time with me on the phone helping to diagnose the problem and explaining how to fix it.  I just followed his instructions and reported results back to him until the gun was running fine.  Most of the problems had to do with differences between my lower and the one he had used to test the upper with.   Ron is so knowledgeable about AR's he was able to take the info I gave him and explain to me what was going on!   He is a genius when it comes to this stuff!
   The debate I had with myself over the last couple of years was which would make the better carbine, 10mm or 9x25.  While the 10mm is probably the more practical round due to ammo availability I felt the 9x25 offered some advantages over the 10 in an AR platform. The 9x25 and the 10 both develop about the same energy at the muzzle with case capacity being nearly the same. But the smaller bore size of the 9 means better gas availability to operate the Direct Impingement system as well as higher velocity at the muzzle. This, along with the better bullet B.C. of the 9 means a flatter shooting piece able to reach out a little further than the 10mm. I anticipate an effective range in excess of 300 meters with good hitting power at that distance.  In addition, I followed Ron's advice and had him install an adjustable gas block on the gas system.  This has allowed me to dial down the gas to control recoil.  That makes for a very nice soft shooting piece that is easy to keep on target.
  As you can see from the pics, I have kept my 9x25 AR pretty basic. My thought on a pistol caliber carbine is to build as light as possible for better portability and maneuverability. I have attached a tactical scope, which my old eyes almost require lately, and I intend to mount a Magpul BUIS folding rear sight. It's a medium barrel with a 35 caliber hole drilled through it, which makes the barrel fairly light. I have not weighed the piece but believe it comes in just under 7 pounds. Recoil is adjustable with the adjustable gas block so the lighter weight feels good when firing the weapon.   .
So far, I have to say I have been very happy with my decision!  The Dillon is very fast out of a 16 inch barrel and just judging by the way it smacks around various targets at 60 meters I have to say I'm impressed.  This thing will toss a 1 gallon milk jug full of water 12 to 15 feet in the air and about the same distance to the rear!
  I am still working up loads for the AR that will be usable in my G20 as well as the AR but my base load so far has been 10.6 grs. Of Longshot behind a 125 grain bullet.  I do not own a chronograph so I don't have exact velocity figures but I believe that load is producing in excess of 2200 FPS out of the longer barrel.
  This higher velocity has produced a problem of its own though as none of the bullets I have used so far stands up to the higher velocity. I have used ZERO, Hornady HAP's and sierra with the same results. Upon contact with a water jug these bullets immediately disintegrate into BB sized fragments.
  Gold dots seem to do a little better and hold up well enough that you can see they penetrate both sides of the jug.  I also have plans to load 125 gr. X-TAC by Barnes and 125 grain Montana Gold 357 Sig.  The MG has a brass jacket and a harder alloy core that may hold up well to the higher velocity. As time goes by I intend to try other options such as 357 magnum bullets sized to .355.  Should be fun!
  If you are a fan of the 9x25 I would suggest contacting Ron and looking into building a carbine to match your pistol. This little round has more than enough power and velocity to make a great intermediate rifle. So far, my experiment has gone well and working to dial in the piece and come up with loads for it has proven to be more fun than I have had on the range in quite a while!


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[The_Shadow]

Mrpipesmkr, Thanks for sharing your build and experiences with the AR chambered in the 9x25Dillon.  I have to agree about the 9mm bullets not holding up to the higher velocities of the carbine, FMJ's would hold together but just penetrate instead of expand.  I suppose the chamber is is cut well and you are not having any issues with case neck or head separations.

I see you mentioned the Zero brand have you tried their 38 super 121 grain JHP 0.356" dia., they have worked well from the pistols in 9x25.  Also with the longer barrel you might try the slower powders to see if you can get even more performance gains.

[mrpipesmkr]

Hey Shadow, thanks for your interest in my 9x25 AR.  I know you have been very involved with developing loads for the round and I have used several of you suggested loads.
  I knew going into my current project that finding the right bullets was going to take some experimentation but that's part of the fun of shooting and reloading.  I have tried the Zero brand in 38 Super .356 and they tend to come apart like the others. I'm thinking the Montana Golds in 357sig may work fairly well due to the stronger brass jacket and tougher lead alloy.
   As I recall you were going to experiment with 9x25 using .357 magnum bullets sized to .355. Have you tried these and what kind of success did you have?  which bullet style and weight did you try?
  Another option I'm looking at is using light weight .358 rifle bullets sized to .355. These should be strong enough to handle velocities in the low 2000's.
  Like you, I enjoy experimenting with something new and look forward to loading up various loads to try out. Slower powder is something I am going to play with keeping in mind that I want the round to be compatible with my G20 as well as the AR. So much more fun than just punching holes in paper!
  Again thank you for your interest and should you come up with anymore ideas please let me know.

[The_Shadow]

Yes, I have to agree that the jacketed hollow point bullet selection is limited and the "bonded" Gold Dots are the better option.  I have searched for the 357Sig Gold Dots, but rarely are they in stock.  I tried other plated HP's but no luck so far.

I have shot some of the 357 110 grain Jacketed Soft Points loaded on the 9x25's without resizing, they worked just fine from my pistol barrel.  Using longer 357 bullets, I think sizing them would help keep the friction down and pressures more normal.

The 357/358 rifle bullets may be too long for the application, or if seated deeper the crimp may be at the radius of the nose section.  My RCBS Silhouette 180 grain cast bullet has too long a nose to use in the 9x25.  I also cast Lyman 125 gr Devastator with its large cavity Hollow Point, and it has been one that I shoot a lot of because they are cheap to shoot. 

The Truncated Cone design's are usually such that the crimp stays on the straight sides while keeping the COAL 1.500" to 1.2600" to fit the pistol magazines.

Its been so hot down here  (97 yesterday) I haven't tested anything in a while.

[mrpipesmkr]

Shadow,
  Thanks for the reply. Your info on the .357 mag bullets is very helpful.  I was looking at trying the 125 grain Hornady's and the 140 gr. from the same company.  The heavier bullet will be a little slower but will range a little better and hopefully be tough enough to stand up to the velocity. I will have to see if the larger bullet leaves enough room in the case for a decent powder charge, I know the 148 gr bullets don't leave enough room for a full charge.  I agree also that I need to resize to .355 and plan on using a luber/sizer to bring them down to size. Will be a few weeks before I can do all this but I will let you know how it works.
  I have looked all over for the 357sig gold dots and cant seem to find them any where.  I guess they are keeping them for their own premium ammo and just not making them available to re-loaders. That's a shame because I had a few that I purchased from Double Tap and they seemed to hold together pretty well. I'll keep looking.
  I don't know that I will be able to try the .358 bullets.  Most of them I have found are too heavy for 9x25.  Someone used to make a 140gr plinking bullet in.358 but they don't seem to be available anymore.
  I'm not sure using a hard cast lead bullet is a good idea with the DI gas system, especially with the adjustable gas block.  Might lead to lead shaving clogging the adjustment valve.
  If I remember correctly, your located in LA.  I'm located in the Dallas- Ft Worth area.  It's been running over 100 degrees here lately and I agree with you that that doesn't make for quality range time !

[Captain O]

Hey Shadow, thanks for your interest in my 9x25 AR.  I know you have been very involved with developing loads for the round and I have used several of you suggested loads.
  I knew going into my current project that finding the right bullets was going to take some experimentation but that's part of the fun of shooting and reloading.  I have tried the Zero brand in 38 Super .356 and they tend to come apart like the others. I'm thinking the Montana Golds in 357sig may work fairly well due to the stronger brass jacket and tougher lead alloy.
   As I recall you were going to experiment with 9x25 using .357 magnum bullets sized to .355. Have you tried these and what kind of success did you have?  which bullet style and weight did you try?
  Another option I'm looking at is using light weight .358 rifle bullets sized to .355. These should be strong enough to handle velocities in the low 2000's.
  Like you, I enjoy experimenting with something new and look forward to loading up various loads to try out. Slower powder is something I am going to play with keeping in mind that I want the round to be compatible with my G20 as well as the AR. So much more fun than just punching holes in paper!
  Again thank you for your interest and should you come up with anymore ideas please let me know.

.

How about contacting Oregon Trail Bullets to see what they can "cook up" for you? Perhaps they can cast a hard bullet that would be appropriate for your carbine.

[mrpipesmkr]

Captain,
Thanks for your reply. I may give Oregon a try, but I've been playing with the Montana Gold 357sig bullets lately and they are holding up to the velocity very well. Although their jacket always seems to seperately the lead slug mushrooms out and stays together for good penetration. I have not tried them in my Glock 20 with the 6 inch barrel but believe they will work with the shorter barrel also.

[DM1906]

I've used Hornady 140 gr. .357" FTX rifle bullets. They are cannalured, which sets the bullet depth near perfect, and prevents bullet pull once seated/crimped. I've resized them to .356 and .355. Neither made any difference I could tell (feel, accuracy or chrono), so I just load them as-is, .357". X-treme 115 and 124 gr. HP's hold up well, too.

[mrpipesmkr]

DM1906
  Thanks for your reply and suggestion. I am especially interested in the Hornady 140gr bullets.  I had thought to try them but had not gotten around to it and believe they will have the advantage of throwing a heavier weight which will generate the same order of muzzle energy at less velocity and have a longer effective range.  I like the idea of the cannalure also because it should help with setback when the round is chambered. Thanks again.
  I use Glock 20 magazines in my AR, do you know if the Hornadys will fit in the Glock mags when seated to the cannalure?
  Do you have any hornady 140gr loads you would share in the 9x25 using Longshot or other powders? Any xtreme loads? Are you shooting them from a carbine or pistol or both? How do they work in the pistol, good expansion?
  The extreme bullets are plated and I have stayed away from them in the AR for fear they might have a negative effect on the gas system if they shed any plating. Any experience with them in the AR.
  Sorry for all the questions, but appreciate the help!

[DM1906]

I understand your concern with the plated bullets, which is why I only use the X-treme (plated) bullets for high velocity rounds, with very few exceptions. I've never had an issue with them and gas ports. The rounds I did a few years ago were for a friend. I developed the pistol/carbine rounds for his LAR pistol and AR, in 9mm WM. The 9x25 loads I developed were for my use only with a LWD Glock barrel. The case capacity and pressure range is nearly identical, between the 9mm WM and 9x25D, so crossing over the data was simple. The best powder for both is, so far, 2400. It offers the best for the carbine barrel length and gas volume, as well as not losing much for pistol use. I can PM starting loads for bullet weights, if you want (I don't publish unpublished loads, especially for custom/wildcats). Sorry, I have none of those bullets left, but they aren't too costly. AA9 performed poorly, by comparison, and was very dirty in the carbine. I haven't tried Longshot with the FTX bullets, but I see no reason it isn't worth a shot, and would expect at least respectable results. I've been using Longshot for other high performance calibers lately, and it's quickly moving to the top shelf.

The FTX bullets will fit in the Glock mags and chamber fine quite long. 1.285", as I recall.

[mrpipesmkr]

DM,
  Thanks for the fast response. I'm going to order the Hornady bullets and give them a try first.  The hollow point extreme bullets interest me also and I will give them a try.  I have load info for 2400 that I can refer to but will put Longshot under the Hornadys first.  It seems to be a great powder fo 9x25 and 10mm.
  Good to hear that I can crimp the Hornadys to the cannalure.  The action of the AR is pretty agressive and anything I can do to alleviate bullet setback helps.
  Thanks again for your info.

[mrpipesmkr]

Yes, I have to agree that the jacketed hollow point bullet selection is limited and the "bonded" Gold Dots are the better option.  I have searched for the 357Sig Gold Dots, but rarely are they in stock.  I tried other plated HP's but no luck so far.

I have shot some of the 357 110 grain Jacketed Soft Points loaded on the 9x25's without resizing, they worked just fine from my pistol barrel.  Using longer 357 bullets, I think sizing them would help keep the friction down and pressures more normal.

The 357/358 rifle bullets may be too long for the application, or if seated deeper the crimp may be at the radius of the nose section.  My RCBS Silhouette 180 grain cast bullet has too long a nose to use in the 9x25.  I also cast Lyman 125 gr Devastator with its large cavity Hollow Point, and it has been one that I shoot a lot of because they are cheap to shoot. 

The Truncated Cone design's are usually such that the crimp stays on the straight sides while keeping the COAL 1.500" to 1.2600" to fit the pistol magazines.

Its been so hot down here  (97 yesterday) I haven't tested anything in a while.

Shadow,
  Just wanted to let you know that MidwayUSA has the 125gr 357sig Gold Dots in stock. I know you've been looking for them, as I have.  I ordered some while they have them. Thought you might like the opportunity also!

[Pablo]

I probably missed it, but how long is your barrel?

How much did Ron charge you for your 9x25 upper? (PM if you like)

I am debating biting the bullet. Dunno if I should get another BCG or not since it SHOULD be the same as 10mm.

[DillonGunner]

Great post. I contacted ron. Gonna order 1 of these ARs myself to go with my g40 w/ 9x25D 7" kkm barrel. Can't wait. Your post led me to him. Good dude.