300 HAM'R, anyone?

[stagpanther]

Looking good!

thanks--hope to finish the build today if the gas tube and block come in--can't wait to fire it. It's windy and rainy, so probably not going to get much meaningful info initially. The more I work with prospective loads; the more I realize the Ham'r is more or less very similar to 7.62x 39; except (hopefully) noticeably more accurate with a better trajectory.

Call me crazy--one of the main reasons I decided to try the Ham'r is that I'm real curious to see how Berger's 115 gr FBHP does in it--it's the best bullet I've tried in the 30 BR so far that isn't an exotic custom-made bullet.

[stagpanther]

Tube and block came in late this afternoon and I hurried the assembly together so I could go out and test. The gas block appears to be a joint development between SLR and Wilson--I've never seen one of these before. I had a couple of jams with the cases failing to eject while trying to find the right setting--I opened it pretty far to get it to successfully eject, but as it turns out the cartridges I put together were likely too under-powered, they produced much less velocity than QL indicated they would.

Here's the very first group of cartridges fired (130 yds)--the 125 gr ballistic tips. I used 1 to get on target and these are the remaining 6. The ES and SD numbers were, in a word, terrible. I'm going to chalk that up to the cases not sealing well to the chamber and/or bullets since I made them from old fired 5.56 stuff. I'm actually surprised some of the shots were fairly close together, so I take that as a silver lining and it's going to get better from here.

Took a deep borescope look at the bore after firing--something unusual I've never seen in a bore before--unless my eyes are mistaken--the tooling marks from the reamer seem to cross cut at an angle to the wall of the rifling (something like 50-70 degrees as opposed to typical 90 degrees).

[jetinteriorguy]

Looks very promising. I’ve always been interested in this cartridge, if I had any use for it I’d be very tempted to build an upper. But for now I have a 7.62x39 that’s got me covered.

[stagpanther]

I've actually developed some "maxed out" 7.62 x 39 cartridges for my AR47 that are almost the same ballistically as what Wilson claims for their optimum factory loads. But I am interested to see if there is an accuracy advantage to the Ham'r. It is pretty soft shooting--so far, but as I mentioned I think my loads were too under-powered. Upon further research I found a statement from the man himself, Bill Wilson, to expect anomalies with brass made from used 5.56, he says typically they need to be fire-formed to headspace correctly. I figure it probably gets a better fit to the chamber as well. Apparently they also say the barrels need quite a few rounds through them before they "settle down" and get accurate. I've heard that from many manufacturers; but in my experience truly outstanding barrels usually shoot great right from the starting gate. Anyway, I ordered 250 factory cases but it's unknown when they'll actually ship even though the website says they are in stock (not Wilson's).

[Shadow9mm]

how did the brass look after firing, necks look better?

[stagpanther]

how did the brass look after firing, necks look better?

Yes, they look fine, a couple of them were slightly dented at the mouth from probably being flipped back into the case deflector--but I can easily fix that. My impression is that the brass in the neck is "thinned out" coming from a 5.56 case--so I'm guessing (hoping) that factory brass is more consistent in thickness.

[stagpanther]

Here's the complete rifle. I'm using the built-like-a-tank SWFA fixed mag scope (I've bashed these things around for many years as utility scopes and they just keep going) for testing; without it on top the rifle weighs in at 6.5 lbs. One thing I've learned the hard way is to beware of intermediate length gas systems--different manufacturers have different ideas what length that is so I buy exclusively Wilson's for their barrels.



I'm a bit mystified by the published numbers I'm seeing for the 300 Ham'r--for example loads at Hodgdon's resources throw way out of bounds maximum pressures in quickload. Quickload itself has in it's cartridge database for the Ham'r 32.20 H2O max fill--but I'm not seeing anything near that in my measurements or what I've seen in other published data for case capacity (my max fill comes close to the useable case capacity). Wilson's ammo is reportedly getting 2,400 to 2,500 fps in 125 to 140 gr bullet weights; I haven't the slightest idea how they are getting that with the powder options I've seen.

[stagpanther]

edit

[ocharry]

stag that rifle is looking good

i have looked through those FWFA scopes..iirc... i thought the cross hairs were a little on the course side for good target work..but then that has been a long time ago...but you are right they are tough scopes

just a thought..if you arent getting published results...maybe buy a box of wilson stuff and see what they are really doing in the velocity department...lol...maybe they are using a 24" barrel for testing...never know..just might be something they are doing that your not....or....they could just be hypin it up some....be a good test though

[stagpanther]

stag that rifle is looking good

i have looked through those FWFA scopes..iirc... i thought the cross hairs were a little on the course side for good target work..but then that has been a long time ago...but you are right they are tough scopes

just a thought..if you arent getting published results...maybe buy a box of wilson stuff and see what they are really doing in the velocity department...lol...maybe they are using a 24" barrel for testing...never know..just might be something they are doing that your not....or....they could just be hypin it up some....be a good test though

Thanks for glam compliment. I'm curious what SWFA scope you were using--I have several of them and the ones I have the reticles are so fine that they are easy to lose in dim light--maybe you were using one with something like a thick duplex?

Anyway, I did some more playing around with powder combos on QL and also looked back on the data I have for 300 BLKout--I think what Wilson might have done is gone with a powder similar to CFEBLK which can be compressed significantly without too much danger of over-pressure while boosting velocities. The Ham'r is really just a stretched version of the 300 Black-out, so I'm going to try a good combo I had for the blackout with a couple of extra grains and see how it goes.

[stagpanther]

I've spent more time studying the loads and test firing some; I've come to the conclusion that the 300 Ham'r is really just a ballsitic reproduction of the 7.62 x 39 out of the 5.56/.223 case. The taper is straightened a bit and the neck length puts .308" at the base of the slight shoulder. Similar to the 350 legend, the options for bullets are very limited by the length of the bullet's ogive relative to the overall length of the bullet; it becomes a "tug-of-war" between the limit of magazine COL capacity, the bullet's base of ogive not disappearing down the case mouth and the shank/base of the bullet encroaching upon case capacity. If you have loaded for the legend or 7.62 x 39 I think you'll know exactly what I mean.

Looking at Hodgdon's load data it becomes pretty obvious that the faster velocity loads are based on compressed loads of either AA1680 or CFEBlk--the later of which can go pretty high in 100+% capacity fill. It also becomes obvious you need to use good SR magnum primers. Yesterday I did a test load of Barne's TSXs using a pretty compressed charge of CFEBLK ignited by my secret stash of Tula gold SR magnum primers that I had left over from before they were banned from import . Chrono numbers did in fact tighten up significantly and a medium charge weight got me to 2,450 fps--pretty sure I can get to 2500 (but ran out of the bullets) as Wilson claims; but I think that kind of velocity is only realistic with a few bullet/powder combos.

In the process of choosing magazines I discovered that the 350 legend magazines I had been using not only cycle the cartridges just fine (not surprising since they are both long 5.56 adaptations) but can get me out to a COL of around 2.3--that helps get a few of the better ogive flatbase bullets like berger's 115 gr seated without the base of ogive getting swallowed down the case neck. Since I spent a lot of money on the barrel and gas components I will continuing experimenting.

[tangolima]

Panther. What make and model of 350 legend magazines do you have? Thanks.

-TL

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[ocharry]

stag..you know it has been a long time..and im sure they make different models with different reticles

anyway the one i looked at was at a gun show on a table..used and i believe it was a 10x....it could have had a duplex reticle i dont really remember...lol...but i do remember i was looking for a scope and those were on the radar...and after i looked through that one i decided those werent what i was looking for..i dont like buying things i cant touch....sometimes you get what you think you are getting and sometimes you dont...so i like to touch one before i purchase

right now im using the Athlon scopes..and they have the fine reticle...and like you said in low light it can be hard to see...in these the reticle is illuminated and that will fix that...i will say that last july i had cateract sergery on my right eye and THAT made one heck of a difference...

anyway.. nice rifle you built and i would like to see your work up to the winner it will become

i will follow along...if you dont mind....lol

[stagpanther]

Panther. What make and model of 350 legend magazines do you have? Thanks.

CMMG's

stag..you know it has been a long time..and im sure they make different models with different reticles

anyway the one i looked at was at a gun show on a table..used and i believe it was a 10x....it could have had a duplex reticle i dont really remember...lol...but i do remember i was looking for a scope and those were on the radar...and after i looked through that one i decided those werent what i was looking for..i dont like buying things i cant touch....sometimes you get what you think you are getting and sometimes you dont...so i like to touch one before i purchase

right now im using the Athlon scopes..and they have the fine reticle...and like you said in low light it can be hard to see...in these the reticle is illuminated and that will fix that...i will say that last july i had cateract sergery on my right eye and THAT made one heck of a difference...

anyway.. nice rifle you built and i would like to see your work up to the winner it will become

i will follow along...if you dont mind....lol

Glad to hear about your eye surgery success; I've been putting it off for many years and know I have to do it eventually. None of of my Medicare plans cover it, though. I've heard good things about Anthlon, they weren't around I believe when I first bought my SWFA's. The SWFA's I have tend to wash-out their color and distort at the very edge of the field of view--but they have very good Japanese quality lenses in terms of clarity and sharpness and come with a very big range of MOA and windrift; along with positive clicking turrets that I never have to worry about moving even though they are always exposed. And they track well. So I sacrifice a bit of a changed view but their over-all built-tough has made them great testing scopes when I'm likely bashing them around with lots of gear.

[ocharry]

yep those SWFA scopes have a good tough rep for sure...i know when i was looking at them REX was liking them for how robust they are..thats one of the reasons i was looking at them..

i just watched a torcher test he (REX) did on one of the Athlon scopes...lol...he acually drug it down a gravel road behind his truck....it had the windage knob twisted so tight against the stop he thought he broke the scope...but as it turned out he figured it out and used a pair of pliers to get it moving and the dang thing tracked just fine..in both directions side to side and up and down...that scope looked like it had been draged down the road too..lol...i have 3 of them and i am impressed..2 have the jap glass and 1 with chinese glass i guess...i think the jap glass is just a touch cleaner...to my eye anyway

anyway get to it..lol.. i am interested in how your rifle gets to shooting and what loads you figure out

[Pumpkin]

stagpanther,
Maybe this is off topic a bit but why not the 30 Rem AR?
That bad boy can move some lead out of the barrel.
I guess new mags and a bolt face would be required?
Your rifle looks sweet!

[stagpanther]

stagpanther,
Maybe this is off topic a bit but why not the 30 Rem AR?
That bad boy can move some lead out of the barrel.
I guess new mags and a bolt face would be required?
Your rifle looks sweet!

Not off topic at all--especially since it's ballistically much closer to the 30BR than the Ham'r--which is actually closer to the 7.62 x 39 IMO. Don't know much about the Rem 30 AR other than apparently it requires oddball bolts and magazines--read someplace that maybe a 30 PPC would be the better way to go since it shares Grendel bolts.

[stagpanther]

I pulled out my old Tac 30/ 30 HRT build with a 18" barrel designed by Harrison of ARP--a master of 6.8 spc and derivatives--and checked my notes. I could get 125 gr bullets up to 2600 fps and in certain "adventurous" loads packing in CFEBlk got to 2,700 fps. I may have to take a second look; haven't fired it in years.

[ocharry]

hey stag i want to make a correction about the scopes i am using....man did i have a brain fart...

i am currently using Arken scopes...not Athlon....jees...what a bone head...lol

sorry for the confusion...i must be loosing it...lol

please forgive me for putting up the wrong info...i get those two names confused all the time....pay attention

[Pumpkin]

That TAC 30/30 HRT sounds like a real hot rod!
Looks like a 30 Herrett without the rim.

[stagpanther]

hey stag i want to make a correction about the scopes i am using....man did i have a brain fart...

i am currently using Arken scopes...not Athlon....jees...what a bone head...lol

sorry for the confusion...i must be loosing it...lol

please forgive me for putting up the wrong info...i get those two names confused all the time....pay attention
__________________
The felon does not fear the police, and he fears neither judge nor jury. Therefore what he must be taught to fear is his victim." - Lt. Col. Jeff Cooper, USMC

No problem--and I've heard good things about them as well.

That TAC 30/30 HRT sounds like a real hot rod!

It's been around in one form or another for quite a while--like the 30 rem AR it just didn't catch on. But I've always like the 6.8 rem spc case as a base for wildcats--adaptable and tough.

[tangolima]

30 arx. Barrel is expensive though. I will stay with .300 blackout for now, mostly subsonic. Just the way I see it, 5.56 brass holds too little powder, especially on AR platform. Ok for small calibers, but would struggle going above 7mm supersonic.

-TL

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[stagpanther]

30 arx. Barrel is expensive though. I will stay with .300 blackout for now, mostly subsonic. Just the way I see it, 5.56 brass holds too little powder, especially on AR platform. Ok for small calibers, but would struggle going above 7mm supersonic.

-TL

Sent from my SM-N960U using Tapatalk

The 300 Ham'r isn't a bad cartridge--it just isn't much of a "walloping" new cartridge as the name suggests IMO. Bill designs good cartridges and knows what he's doing and the Ham'r makes for a good close range soft recoil AR hunting cartridge--but I think the odds are pretty good it could also fade into obscurity. Just my less than 2 cents.

I looked the ARX up--it looks like it'a almost the same as the Tac 30/30 HRT in performance numbers. However, IMO (and it's based on messing with wildcats based on both the grendel and the 6.8 spc)--both the case and the bolt for 6.8 spc cats are generally stronger than those based on the Grendel.

[stagpanther]

Had to dig around some to find it--but here she is--a genuine ARP Tac 30 that I put together (which Harrison initially called 30 harrett). I never did try the berger bullets so I think I'll give them a whirl and then see how it compares with the 300 Ham'r.

[tangolima]

30 Harret has rim. 30 HRT (Harret Rimless Tactical?) is the rimless version.

-TL

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