A while back I picked up a Spike's Tactical .22LR Upper and shortly after getting it I realized it would cycle subsonic ammo, which meant I needed a suppressor.  After picking up a .22 Suppressor I have had tons of fun with that rig as well as several other .22's I have threaded and used with the suppressor.

After a while I wanted something bigger.  Some research on the subject of suppressed AR's led me to the 300/221.  I had never messed with a wildcat before and I didn't know anyone around my area that had played with this cartridge.  It was a little daunting but I decided to give it a go.

I knew I wanted a short barrel, the ability to shut off the gas for ultra quiet shooting, a side charger with the handle on the left, and a QD suppressor I could also use on 223.

Here's what I ended up with:
RRA registered SBR lower (my patrol rifle lower, it wears an 11.5" in 223 at work)
ASA sidecharge upper
Noveske 10.5" 300FB barrel
Paladan Machine 3-position gas block (open/restricted/closed)

I had to have the barrel turned down so it would take a .750 gas block in the pistol position.  My research led me to the conclusion that I had to have the short gas system for reliable cycling of both supersconic and subsconic rounds and only a .750 Paladan gas block would fit under a free float handguard.  I went with a YHM because it gives me access to the slotted screw that is used to cycle through the 3 positions.

I also picked up a set of Redding 300/221 reloading dies, a form and trim die, and a Forster power trimmer to make brass from 223 and reload it.

This project has been over a year in the making and I finally have a working rifle!  Here are some pics.

The gun:


The gas block:


The ammo:


I've worked up a few loads I'm happy with.  Using Sierra's tables I started with a 110gr Sierra Varminter.  I ended with using 16.0 grains of Hercules 2400 to get an average of 2050 fps.  I then played around with the Sierra 240gr SMK's and had to back off to 8.5 grains of the 2400 to get an average of 1040 fps.  After that I decided I wanted a better bullet in the 110gr range so I loaded up some 110gr Hornady V-Max's.  I get 2100fps with the same 16 grain charge of 2400.  The supersonic rounds cycle the gun with the gas port in the restricted position and the subsonics cycle with the port fully opened.  I only bought the 2400 because it was all that was in stock locally that Sierra had used making its tables.  I had such good luck I'm not sure if I'm gonna bother with any others.  Well, I'm sure I will since that's what's so fun about it.

Accuracy has been good so far (about 50 rounds through the gun).  All groups have been a ragged hole but I've only shot at 25 yards so far.  I have more space but the field at my house is way to muddy at the moment (corn field).

I'm very pleased and am anxiously awaiting my YHM 7.62 suppressor.  The ATF has my money and I'm just waiting on the stamp so I can go pick it up.  I can't wait.  

Overall I think this is a very cool little round.  I'm getting more muzzle energy with the 110gr bullets out of a 10.5" barrel than I get out of my 18" barrel with 55gr .223 XM193 with less powder.  I'm sure this is due to the faster burning powders used and the small shoulder used on the 300's.  I also think I could get another 100 or 150 fps but I'm not sure I want to push it.  After all, the whole point was the big subsconic rounds for suppressed shooting and I don't want to beat up the 1:8 barrel with alot of hot supersconic ammo.  

Still, this would make a wicked CQB gun if the 110gr V-Max's perform well at these velocities.  They are the bullet recommended by Hornady for Police sniping in their 308 TAP line to prevent overpenetration with head shots, but they are moving quite a bit faster.  I read in another thread recently that the 110gr V-Max is supposed to expand down to 900 fps, but I haven't verified this.

good stuff.  fun caliber isn't it?

here is my 300/221 AR:



I'm currently building a bolt gun whisper as well.

I've considered a bolt gun as well.  I'm normally a Remington 700 guy but I've heard that the 700 has issues with ejection of all things.  I don't know why the 300 would cause ejection problems, and that's just what I've read, but it does give me pause.

I've only thought about this direction and haven't really taken any steps toward building one.  What platform did you decide on for your bolt gun build?

I love it !

I got a new Ron Williams 10 1/2" ( Pacnor Polygonal 1x8, same blank as Novelski ) and a Palladin 3-way gas block with lever off the EE about 6 weeks ago and Redding dies and forming die rom Midway.  It has been fun and easy to make the brass, have had no issues at all.  I made my set-up light and easy to carry for hunting.  I have a YHM 762 that I use on my AR 762x39, 16" barrel , but wanted to use my YHM 9mm Wraith XL on this and the barrel had just the thread I wanted and is a big difference in weight.  The 300 Fireball is very effective, I have taken a 9 point buck and 5 hogs with 3 head shots.  The animals don't just run off when the first shot is fired.  The last 3 hogs I killed was in the same group of 4.  I have tried different powders and the ones I like are  150gr FMJFB-6.5gr Blue Dot,  168gr Match-6.5gr Blue Dot,  175gr FMJBT 6.5gr Blue Dot,  Speer 200gr SP- 9.2gr Lil Gun, and Horn 220gr RN-9.5gr Lil Gun.  I will mainly be using the Horn 220gr, the others were misc. bullets to experiment with.

Good to hear she is working out for you

CZ-527

Just started that project.  Have the rifle and reamer, but havent ordered a barrel blank for it yet.  Initial attempts to remove the factory barrel in my 6" bench vise proved fruitless, the barrel will need a proper barrel vice in order to come out, it is TIGHT.

Good info, I havent hunted with my whisper yet, but I want to.  I've pretty much settled on the 220-240gr bullets and Lil Gun.  That combo cycles the action nicely with the 8" barrel and the gas system length I am using (pistol-ish)

Track down some Lil'Gun powder.   Its great in 300.

Nice Rig.  I just got  my whisper bbl in the mail Monday.

OP, could you measure the ID of your FF tube for me, please?

Still trying to figure out exactly how I'm going to build this one.

Thanks

I have some on order.  In fact, based on what I found on quarterbore (great 300 resource BTW) I planned on trying Lil' Gun and AA 1680 as both seem to work well in AR's.  When I ordered it at my local shop they happened to have a pound of 2400 on the shelf.  It was listed in the Sierra and Hornady manuals so I figured it would give me something to play with until the other powders came in.  I figured it would not cycle the gun for me since it wasn't highly recommended for my application.  Much to my surprise, it has worked quite well.  I didn't cancel the order for the Lil' Gun or the AA 1680 because I figure why not try some others.  It will be interesting to see, if they all cycle the weapon well, if they are much different in my ability to suppress them.  Time will tell.

Great guns you all, Ive been promising myself to finish my .300......Maybe ill be able to get a novenske if they still have barrels in stock.

ID is 1 3/4".  That seems to be the standard and was why I couldn't use the Paladan 3-pos block designed for a .875".  It required 2" of clearance and I couldn't find a free float tube that would work.  The barrel was .750 where the carbine position would have been and .875" where the pistol position was.  I had ADCO turn it down to .750 in the pistol position and .700 in front of the gas block so I could use the smaller gas block in the pistol position.  The only problem, which I didn't think of until I got it back , was that when they turned down the end of the barrel it removed the barrel serial number and Noveske's emblem.  I'm sure that won't help resale value, but since I'll likely keep this until I die it isn't a big deal.

Thanks for the info.

I like that YHM Customizable Round Handguard, I have one one my 16" Lightweight GO TO Gun.

This is the first customizable one I've tried.  I just got everything together for testing so I haven't bothered to bolt any of the rails to it.  My only concern would be putting a VFG on them as the rail is held on by fairly small screws.  Have you tried this and are they sturdy?

I decided on it for this build because the slot lines up with the gas block adjustment and I have several YHM light quad rails that I really like.  So far I am happy with this one too.

Has anyone tried a gas piston system with the .300 Whisper?

This question came up on quarterbore, here is the thread:
Piston 300 Whisper

There weren't many replies and it sounds like Marty at Teppo Justu tried one with limited success.  If Marty couldn't get it to work well, it must be a challenge.  

I never considered it as I'm not a fan of piston AR's.  DI's work well and are simple, so I don't mess with the non-standardized piston stuff.  YMMV

Most (if not all) of the piston systems were designed with the high pressure, high gas volume of the .223 in mind.  On the .300 Whisper, it becomes challenging enough at times to get the standard DI system to function reliably with the subsonic rounds.  Even with a piston system for a pistol length gas system, we found that the design of the piston system restricted gas flow from the block to the piston enough that it would not budge the carrier.  The same load, in the same barrel, with a DI system cycled violently enough that it ripped the rim off the case and therefore required an adjustable gas block to tone down the gas flow...

In short, it PROBABLY COULD be made to work, but not without tweaking the piston components...

That said, we built a 16" 30 HRT with an Adams carbine piston system and it runs the 110s at 2650 and 240s at 1080....

There you have it, the guys on quarterbore were correct.

Marty, I've been meaning to ask you about the .30 HRT.  I've read alot about the new 6.8 SPC II chamber spec allowing much higher velocities, nearing 3000 fps, from the 6.8.  Would the same changes (increased lead and different rifling) make the same velocities possible with the .30HRT?

To test that exact theory we have a new reamer and some 12 twist blanks... hope to know more soon

Congrats on your 300 project coming to life.  What's the mag capacity (reliable and reloadable with bolt foward) using the Pmag20s for the 300-221?

Since the 300-221 Fireball case has the same tapper as the 223/5/56mm.  So a  223/5/56mm 30-round mag will hold 30 rounds and a 20-round will hold 20 etc...

In fact I have used my 300-221 fireball with a fully loaded beta-C mag.

320pf

I got the following question by IM:



I figured I would answer it here in case others wanted to know.  My handguard is the Specter length (9.625").  I chose it because almost all of the unthreaded barrel is under the handguard.  When I put the QD attachment for the suppressor on there was barely enough room to get a slim wrench in to tighten it.  With the suppressor on it will almost touch the handguard (I think I'll have about 1/8" clearance).  I will post a pic when I get my suppressor (I hope very soon).  

If you are getting a 10" barrel the mid-length (9.2") handguard should give you a very similar setup that is just 1/2" shorter than mine.   I would measure and make sure though.  I got my barrel first, mounted it to the upper and measured out to the threads, then purchased the appropriate length handguard.

I haven't loaded more than 10 rounds at a time yet (just making shot strings through the chronograph) as I've been in load testing so I can't say for certain.  320pf, however, has been one of the posters that I've seen routinely while researching this caliber here and on quarterbore and he knows what he is talking about.

Any feedback on the ASA side charger ?

It is a beautifully crafted upper.  The parts fit well and the action is very smooth.  I like the side charging handle very much but it does take some getting used to if you are accustomed to a standard AR.  I chose it for this build for a very specific reason, to cycle the weapon with the gas turned off while prone using a bipod.  It is also very handy for not having clearance issues with a scope.  Since it is non-reciprocating you don't have to worry about getting your fingers in the way.  I'm also hoping it reduces gas blowback by my face while shooting suppressed.  Since there is no charging handle at the top it should be better, but I won't know until I take possession of my suppressor.  

It does make locking the bolt open manually (as you would for a double feed clearance drill) a bit tricky and when you rack in the first round it is a good idea to fold the handle back down afterward, but these are minor to me since it fills my specific need.  I won't be using one on every AR I put together (the ASA side charger is a bit pricey) but if you want something unique and well made, it is a good choice.  I think it would make a great upper for a long range build like a 6.5 Grendel.

It is great for suppressed for all the reasons you stated. Function, manipulation from prone, gass blowback to the face...

Old pic from years.... ago.



I recommend ALWAYS slingshot the charging handle. If you keep your hand on the handle as it goes forward, there is a good chance that the bolt hold back/release button will bite you. As the handle passes the BHO it can pinch the bottom of your hand.

-3D

I just got my suppressor today!  I hope to have pics and range report soon.

Be careful when releasing from the locked back position - as the bolt catch is in the path of the charging handle...  

There are some who have voiced concern for right handed shooters with suppressed rifles in that you do have a large opening in the side of the upper right by your face but I have not heard of anyone complaining.

Thanx , thanx , and thanx . . .

I don't have a proper range report since I didn't have much loaded ammo.  The call from the gun shop saying the paperwork was in was a bit of a surprise and with it being Superbowl Sunday I didn't spend my time reloading.  I did fire the rounds I had already loaded and I am satisfied with the combo.  While it is definitely louder than my suppressed .22 (which I expected of course) I was shooting the rifle on my back porch I didn't need hearing protection and my family in the living room was unable to hear it at all.  That is more than acceptable to me.

This might just be the coolest setup I own!  I'm having alot of fun with this, in case it wasn't obvious

Pics with suppressor:

This is a good point.  If I manually cycle the bolt and it locks back, I push the handle forward and fold it in.  That way, when I push the release the handle is already forward and this isn't a problem.  If you leave the charging handle to the rear it will slam forward, just like what would happen with a normal AR, but the finger you use to push the release will be directly in line with the charging handle as it slams home.  If you don't push the handle forward as I do then I would use the handle to release the bolt when you put in a fresh magazine, much like it is taught to pull the slide on a handgun as opposed to pushing the slide release lever.

Well I have to say that this is a great thread. I, too, would like to get into the 300 Fireball game. I have been considering the barrel made by the member tp555 on quarterbore.net. I think he makes them to whatever length you want, but I have been discussing 10.5" with him.

I have also been looking at the YHM 7.62 suppressor. Altair, can you comment on the weight and balance of your rifle with the suppressor mounted?

Looks like the perfect setup you got there!

Thanks for any info you can provide
jonblack

Just wanted to mention the guy called tp555 on quarterbore.net is the same guy as Paladin Machine Service. He gave me a quote on a stainless barrel, adjustable gas block, gas tube, and chamber gauge.

Thanks
jonblack

tp555 = Paladan Machine and he was a good guy to work with.  Very quick responses to my questions and delivered a quality product as advertised.

The YHM can is stout.  It is managable because it is on a short, light rifle but you definitely know it's hanging on the front of your gun.  It is designed to handle the pressures of heavy .30 caliber rifles and is a bit overkill on the .300 in subsonic.  I chose it because I wanted the flexibility to use it on my 300 (subs and supers), my 308's, my .223's, and whatever else tickled my fancy.  If you are shooting dedicated subsonic 300's only, alot of guys have had good luck with 9mm pistol suppressors which weigh about a pound less.  I just couldn't use the 9mm can on my other full power rifles and I couldn't afford both suppressors.

In the end I guess it depends on what you want.  One of best features of the YHM can was that it threads onto the QD .30 flash hider (5/8-24) and the QD .223 flash hider (1/2-28), making it work on most everything I own.  I am very happy with it, especially for the price.  

Altair

Thanks for the reply. Sounds like I am in the same boat as you are. I have a .223, an AK, and a .308 that I would like to use a single can on. But, I also have a 9mm AR and a Glock host that I would like to suppress as well. So, in the end, my plan is to have a .30 can and a 9mm can. Now, if I can figure out how to make the threads so that I can screw the .30 can and the 9mm can on the .300 upper, that would be ideal. That way, whichever can I get first I would be able to go ahead and use.

Again, I am really pleased to see this info here. I recently joined quarterbore.net but I like the larger community here on ARFCOM.

Thanks again
jonblack

Altair,  The current 300 fireball barrels that Noveske is selling have the gas block in the pistol position.  Did you have to move your gas block back to this position, or did you just have to turn down the existing pistol position to .750"?

My barrel came from Noveske with the gas block in the pistol position.  It was one of their low profile blocks designed to go under a handguard and the setup was fine.  I didn't use it only because I wanted one of TP555's 3 position blocks.  My barrel was .875" IIRC where the gas block was (pistol position).  TP555 makes a 3 position block in the correct diameter but it would have needed a 2" inside diameter free float tube to go under.  I couldn't find one.  All the ones I came across were 1 3/4" inside diameter, which would accomodate TP555's .750" gas block.  I just turned the barrel down to use the .750" block.   The barrel had a flat in the carbine position that was .750".  I suspect this profile was used to make both pistol and carbine length gas system barrels.  I just needed the .750" block to go back to the pistol length and a reprofile was the simplist way to get to where I wanted to be.  It beat trying to have a custom free float tube made for sure.  

I hope me explenation makes sense and didn't further muddy the water.

Thanks,  now I understand!

The barrel is not cheap and it would seem mandatory put a switchable regulator there because of the large pressure differences between subsonic and supersonic loads.  Before you put the 3 position regulator on did you try the stock barrel block with loads at extreme opposite ends of the performance envelope?  Like say, a supersonic 125 gr hot load and a 240 gr subsonic load?

Mongoose

I am not sure if you know, but the guy known as tp555 who makes the adjustable gas blocks also makes custom barrels to your specs. You can get the whole setup turnkey. His barrel, gas block, gas tube, and custom chamber gauge, cost about what a Noveske barrel costs. His work is highly regarded over at quarterbore.net.

Hope this helps
jonblack

I didn't try both types of loads before changing the block.  I knew from the outset that I wanted the ability to shut off the gas and the ability to have a 3 position block with high/low/off was exactly what I wanted.  That said, my gun will cycle with the gas block open (unrestricted) with both subsonic and supersonic loads.  If I had a standard gas block it would work with both.  I feel the rifle is overgassed, however, with the supersonics this way and it is easier on the system to use the restricted setting for the supersonics.  

I agree that getting a complete barrel/gas system from tp555 would be a good way to go.  In fact, if I build another 300 that is almost certainly what I'll do.

tp555 is running 5 weeks behind.  I have a 3 position 0.625" diameter block on order from tp555 for an A1 style .223 project that I decided not to build.  I will probably put it on the EE when it arrives.  

You say 5 weeks like it's bad.  I've had a Del-Ton kit on order since January of 2009 that isn't here yet...

Yeah I'd rather wait 5-8 weeks for one of his quality barrels and gas blocks than 6+ months for a M1S 300 Fireball barrel...

Did you consider this forearm tube from Midwest Industries for the 0.875" gas block?



I have one of these and I measured and calculated the actual radius to the inside of the square notch that forms the picatinny rail at  approximately 1.07" (or the equivalent of a 2.14" ID handguard.)  It would really be sweet because the large holes in the handguard should make switching gas positions easy.

The problem would be that I would have to install the gas block after I tightened the handguard in place. That might be rather difficult!

I'm not familiar with that MI model of handguard.  I asked the question here and on quarterbore "who makes a FF HG with an ID of 2" or more" and nobody suggested it and I never came across it.  Regardless, I'm not sure how practical putting the block on after the handguard would be.  If you could pull it off, however, it would save you the trouble of changing blocks and reprofiling the barrel.  If you decide to go with it let us know how it works.

I believe MI just came out with this model recently.

I got my 0.625" 3 position block from tp555 today.  However, there may be a problem with it.  I told him that I have a 0.081" gas port hole, but on my reciept he wrote, ".070 gas port".  I emailed him for clarification.  I am going to wait and see how he handles this order before I contact him about making me a 0.875" ID block for a 300/221 Noveske barrel.


Edit to add:  tp555 said that the '.070" gas port' was in reference to the gas block in the "resticted" position.

Any of you guys w/a recently purchased tp555 bbl happen to know your chamber dimensions?   I had asked as for a chamber cast when I ordered the bbl and was informed that he did not do that.  I should have asked for a reamer print

off hand, no...
but i do know that he uses use a clymer reamer.  It is their standard 30/221, which is the 1.4" length

Thanks, I'll see if I can find something on it.