Home Forums Hunting & Shooting AR and Tactical Rifles 358 Herrett AR - 35 Rem in the AR15

Yeah I had done the same thing before this .358 herrett, still have a couple dummy rounds made from straightened 5.56 cases, they look kinda cool with an old school 200gr RN bullet seated in them.

It can feed from 5.56 mags - magazine modifications are the same as needed for this 358 - just remove the ribs. In a metal mag I mill out the rib section; in Pmags (for 5.56 cases, not the 6.8 case I'm using for the Herrett) you can file out the rib from inside. They work great once that's done. I'll post a pic later.

A couple pics, sorry for the potato quality.
The 10.5" is on an SBR lower. You can see the magazine cut visible where I removed the ribs; I need to cover that on that mag. On the shorter mags as shown in the 16" carbine, the cut stops at the bottom of the lower's magwell opening, so the cut is not exposed while the mag is in the gun. Probably not ideal for really dirty environments, but it works well for normal wandering around in the woods.

Here are a couple more shots of the magazines, showing why the rib cutouts are necessary. Same goes for a straight wall 35 cal, unless it's short enough so the bullet ogive contacts the rib at the .250" diameter point like supersonic 300 Blk.






Also shown here is a .30 cal AR15 wildcat I made up using a spare Ruger 30/06 barrel - it's similar to the 358 Herrett in that this one uses 30 Herrett dies and the SPC case. In a 20" barrel it pushes the 125 NBT to 2725 fps, and various 150gr SP bullets to 2475 fps. The rounds in this pic are loaded with the 130gr Mk319 SOST bullet to 2700 fps.

Excellent cartridges!

Yondering; I have your 30 cal set up and am moving in the 35 cal direction. I purchased a 224 Valkyrie reamer that I plan on bushing up to 35 cal for the chambering. I don't know much about gas ports, but when that time comes, I'll pick your brain again. Rather than shortening 357 Herrett dies I'm gonna get a set of 224 Val bushing dies and use a .383 or .384 bushing for the 35 cal neck. Maybe by then 350 Legend mags will be in abundance and I won't have to modify 223 mags.

What is your 30 cal version? You don't have mine, since I've only made one barrel and made the reamer myself, but there are others that are similar. BHW's 30 American is the closest.

I don't think I'd want to go through the trouble of bushing dies and the Valkyrie reamer + some other neck & throat reaming for this cartridge, but it'll be interesting to see what you come up with. The Herrett reamers and dies are available and just work, so it's really the simple way to go without compromising anything.

Don't try to use 223 magazines (or the 350 Legend mags) for this cartridge, you'll have endless headaches with feed issues because it's based on the 6.8 case not the 223. The larger 6.8 and Grendel cases both need their own magazines; they don't work right in 223 mags. 6.8 SPC mags are plentiful and it's not very much work to remove the ribs.

I thought I bought the barrel from you. I'll have to think on that a bit to try and figure out where I got the barrel.

Not from me - that I remember. I think you might have asked me about it way back when, but I've only ever made one of that 30 cal and it's still in my safe. If you asked me for recommendations back then I probably said to go with Black Hole Weaponry.

What about Dead Shot Barrels, it might be from him??

Never heard of them before, sorry.

AR15 Performance has the 30Tac or 30 Herrett based on the 6.8 Rem and it looks to be the same. He has barrels in stock that are of exceptional quality and performance.

Except for the one I got from him. It was a train wreck, as was his response and all the interactions with him about it. Never again.

And - it is similar but not the same as my 30 cal. I learned from the mistakes in his barrel and developed something better for my own use.