No, I'm not Bill but these are easy questions.
1. I would say it is more stretching out a 5.56 instead of a 300BLK.
2. The when the project started it was base around improving the 7.62x40WT
3. The goal of matching the 30-30 was met.
4. Keeping the 5.56 case allowed the conversion without having to change the bolt.
5. A side note could be that when the project started LC brass was everywhere and could be had for next to nothing!

I had it in my mind that the 30-30 still had about 200fps on the Ham'r.. now that I look at some 30/30 data, I see it's much closer than I thought. I think of the ham'r as a blk with longer brass and lighter bullets. The brass length was what I meant by "stretched".

Haywire, Graycard has pretty much covered it. If you shoot factory 150gr .30-30 ammo in the same barrel length the HAM'R velocity is equal with the bonus of better BC bullets. It's "possible" that a necked up 6.8 would give more velocity, but you lose the stronger and more common .223/5.56 bolt compatibility which was a biggie for me. Another plus is more magazine capacity.

The HAM'R is capable of cleanly taking more than deer and hogs. Bill has shown that with elk and lots of African game. I've taken multiple moose and grizzly. With the right bullets and loads 300 yards on game is within reason, IMO. The little engine that could...

I have a 30HRT as well. It does get 100 fps or so over the HAM'R in most cases, but in my experience, the brass quality and vast availability of the 223 case, and a stronger bolt make the HAM'R design a better choice for AR platforms, again IMO. The HAM'R hits the 30-30 goal, the 30 HRT surpasses it somewhat, but with the issues mentioned.

My last comment was a bit long and covered trying several things, but I did have a few questions...

(1) With nickel cartridges and no flare, is it the seating of the bullet or the crimp that could cause the case bulge? Never had this problem with any other cartridge but admittedly never used nickel cartridges before.

(2) General Question about shift in POI. I just don't see how one bullet or load can shift more than an inch at 25 yds. More at 50 yds. What exactly allows this to happen? In this case, the lower velocity (1800 fps) were hitting a full 1" to 1.25" low at 25 yds. Baffles my mind.

(3) Has anyone tried any other Medium burn common powders for plinking? Looking for powders that are keep it simple safe 1800-2100 fps and full case fill. I should be good for awhile as I have lots of 7.62 x 39 but not gun in that chamber. I don't mind breaking them down 20 at a time at the cost of a primer.

Thanks.. John

I totally agree with what can be done with a 30-30, I seem to remember Teddy Roosevelt talking about an African trip with it and comparing to the calibers before. I also have a friend in Alaska who has taken all with the 30/30. Note: he would not hunt grizzly without a backup hunter and a much larger gun at the ready. IMO bullet design, weight and impact velocity have to be within a range of comfort, different for everyone. If I were to go bigger on game with 300 Ham'r, it would have to be the 150 gn, bonded or eq, 50 yds and as close to 2100 fps impact (+/-), and you have to be ok with expiration 3-5 minutes later, just IMO. To keep this general concept as the range extends to 100,150,200, 250... the minimum cartridge gets bigger to put more powder behind the bullet and/or use a bigger, more efficient bullet. What I like about the 130 gn is that the velocity of 2500 gives a good point blank out to 150-175 yds for everything I am going to shoot.

Slightly different tack, in Alaska many carry pistols or 12 ga for defense. The ham'r rifle is light enough that I think it would be an improvement on the 12 ga slug, if you can count on multiple rounds of heavier non-expanding deep penetration, head shot. I have not been there for years and used to carry a 45 colt with solids, only good if the barrel is in the mouth when you pull the trigger. The Ham'r would have been much better.

#1 I always flare the case mouth with a Lee Universal Neck Expanding die available from Amazon or WC, this eliminates the issue. I also taper crimp with ether a Dillon or Redding Blackout taper crimp die.

#2 I typically see a POI shift of up to 4" at 100yds depending on the load and don't see this as excessive. I usually see more with 5.56. I do have some loads that shoot the same POI in specific barrels.

#3 Suitable powders for the HAM'R is a short list...
A1680 or CFEBLK are the best all around
SW Black or SOCOM have some applications
Functioning loads can be made with IMR or H4227, A5744 and Norma N200, but they are too bulky for top velocity
Faster powders like W296, H110, 11FS and LilGun build dangerous pressures too fast and don't generate enough energy to function guns with mid or intermediate gas systems.

The only gun I blew up in early testing was with 11FS !!!

Alaska and bears produce more than their share of lore, that's for sure. Not many that spend a lot of time outside carry a 12ga, not for long anyway, unless they're required to for work. After enough time, the weight generally gets it left behind and probably replaced with a handgun. A HAM'R would be very effective for bear defense, but no need for solids, normal hunting loads would work fine.

Thanks much! I'll incorporate all of #1 and get a neck expander and taper crimp. I just finished a batch and being gentle had 1 bulge in a 100 that I had to fix. A slight flare should end issue.

Playing with the zero of this rifle and a 2.7" over bore mount, I'm now thinking of going with a 75 yd zero or .5" low at 50 yds. This would give perfect zero from 50- 125 yds and within about 1 inch from 25-150 yds. 200 yds would be around 4" low (1900 fps, 1000 ft-lbf). That would work for me.

I zero 1" high at 100yds (basically a 150yd zero) with day scopes and dead on at 100yds with thermal for night hunting

I loaded up my first test load for 300 HAM'R, using the loading data on the June 29,2023 update reloading data that everyone seems to reference. Having only been reloading for a year and my only rifle cartridge being 300 AAC, I took a pretty caution approach. I have an AeroPrecision converted 5.56 by using the WV 16" RECON barrel. Having had great luck with the Lehigh Controlled Chaos in 115 gr, I chose the CC in 125 grain and am starting with the Hornady 125 gr FMJ to get a feel for the cartridge before loading up the Lehigh bullets.

The parameters for the load are new Starline brass, CCI 41 primers (the mil version of the CCI 400---magnum primers are very difficult to find at a price you can afford), COAL 1.255 and CFE BLK for the powder.

Unlike most of you in Texas, my range is at 3000 MSL and the OAT was 32 degrees. Yes Montana gets high and cold. :-)

I reload with a Dillon 550C although for these test loads, I use it more like a single stage press......the cases are sized and primed....each powder charge is weighed and hand loaded, then seated and lightly crimped, using a separate seating and crimping die. Each round is inspected for primer seating, etc. I know it is awkward on a multi stage like the Dillon but it works great for small batch loads.


When I do a new cartridge, I always load the min load so that I can compare my actual results with the published results. For this round the published was 24.3 gr CFE BLK with a velocity of 2200 fps. My test results were very close to the published results.

Rifle Cartridge, 125.0 gr 24.3 gr CFE BLK
# Speed (FPS)
1 2242.9
2 2232.3
3 2211.7
4 2190.8
5 2197.9

Based on those results, I decided to start my actual test loads with 25.0 grains of CFE.

As I worked the load up in .2 grain increments all was going well. At 25.8 grains. here is the result

Rifle Cartridge, 125.0 gr CFE BLK 25.8
# Speed (FPS)
1 2350.1
2 2357.3
3 2362.4
4 2364.6
5 2362.4

AVERAGE SPEED 2359.4
STD DEV 5.2
SPREAD 14.5

I was incredibly impressed with the accuracy of the barrel and at this powder load the STD DEV of 5.2 seemed great. At 26.0 grains, it turned sour.

125.0 gr Hornady FMJ *
# Speed (FPS)
1 2399.3

This first shot felt a bit snappy and when I inspected the fired case, the primer was pushed out slightly. I packed up my new Garmin Xero C1 chronograph and headed home.

I understand the differences and all the variables. The published max velocity was 2450 fps and a load of 27.0 grains CFE BLK. The two differences, other than altitude and temperate are the CCI 41 primer and the Starline brass.....as opposed to the CCI 450 magnum primer and the SIG case. I noticed a comment on another thread that the Starline brass had less case volume. Is the case volume difference between the Starline and Sig brass significant enough to cause the pressure difference I seem to be experiencing. What looks to be a good load at 25.8 is well below the powder load and 90-100 fps slower. With this same Hornady bullet in 300 AAC I am getting right at 2200 fps. The increase using the HAM'R is only about 150 fps.

Any input is greatly appreciated.

After more research....it seems the issue might be the CCI 41 primers instead of CCI 450......More checking to do!

A coworker of mine said that in his experimentation, he saw better velocities with standard primers. 🤔

The Starline cases do have less powder capacity, approx .2gr less and you will normally get comparable velocity with this .2gr reduced charge compared to a Sig case.

All around I prefer CCI450s and that is what all of our factory ammo is loaded with, however I've had good luck with standard CCI400s too. I even use Fed 200s when loading for my bolt guns. I don't have a lot of experience with other brands of primers and wasn't happy with the accuracy I got when I tried CCI 41s.

Back when you couldn't beg borrow buy or steal primers I used some Remington 7 1/2 primers in my 5.56 loads with the result being the velocity went down slightly but the accuracy went WAY up compared to using CCI 41. Haven't tried that with my Ham'r yet so if anybody does (or has) experiment I'd be interested in the results.

I used the Remington 7 1/2 primers while loading for my 7.62x40WT for years before the 300 HAM'R came out. The only problem was they felt loose when seating them. I switched over to the CCI 400 and 450's and that seemed to solve the problem. That led me to testing out every primer I could find.
Now! Can anyone tell me where I put the information?

It's in that 3 ring binder labeled "reloading info" on the shelf above your reloading bench... there on the left.

Reloading question!!

so, I've been shooting the hamm'r off and on for a couple years now, and largely I love it. however, I've been getting inconsistent ejection. I'm assuming it all has to do with the ammo I'm shooting. I'm using a home built upper using the 11" barrel and an adjustable gas block. I had to open the gas block a considerable amount early on because while it mostly ejected, I'd get a few that didn't. now that it's open a lot, everything ejects, and most of it goes in a nice pile, 5 oclock, about 10-12 feet away. However, I get a few at the 3 position, and a couple that just barely come out and head about 130ish. I'm shooting suppressed, but I think the cause is this:

I'm fire forming cases made out of LC nato brass I cut down and resized. I'm using 25 grains of 1680 under a 125 grn TNT.

Am I just getting inconsistent pressures because some of the gas is slipping by before the case can seal the chamber? Will my issues go away once I start using actual ham'r cases? I've never fire formed using a semi auto before. It's always been in a bolt gun.

Does it happen on previously fireformed cases or just during the fireforming process?

My best shooting loads use IMR 4198. My rifle doesn’t like CFEBLK at all . I just now have loaded some 125 TNT with 1680 but have not shot them yet. Speer 130’s and 4198 leaves the pigs DRT

All I've shot so far are fire forming loads. I've shot about 500 or so of them, and they are accurate, and lethal.

I'd load some up on your fireformed cases and see how they function.

There will soon be a new kid on the block....available in mid May (NRA show release)

Wilson Combat NULA M20S mini action (MSRP $2995.):

Bare rifle with 16.25" barrel weighs 4# 7oz
6# 3oz ready to hunt with Leupold 3-9x33 Ultralight scope, mounts, Silencer Central Banish Backcountry suppressor and 6rds of ammo
5 + 1 capacity
3 shot 100yd group with the new Lehigh 110gr TXC

Nice!!! Good thing Tractor Supply has a sale on their gun safes.