I have noticed one thing that is relatively consistent when it comes to those that get into reloading. We are tinkers. As I was sitting at my reloading bench pushing out some 7.62×39 on my RCBS rock chucker 7 I couldn’t help but look over at my RCBS single stage setup for 308 wincher (308win) and think why not reload some subsonic 308. This thought came as I was thinking about my IWI Tavor 7 and the 30 cal IWI suppressor I had just gotten in. Why not make a subsonic load for that gun and have a little fun.

Gotta Slow Down

For those that do not know, 308win is moving around 2,500 feet per second (FPS) on the low end and 2,800 FPS on the higher, for commercial ammunition. The sound barrier is approximately 1,125 fps, so we are trying to drop our 308win down below that. In the past I have found that for my 308win firearms ammunition moving around 950-1,000 fps is stable and accurate, so we are going to be going for that range with our reloads. I used to put a statement here that “I shouldn’t have to say this, but I will” and then put a safety disclaimer in the paragraph. However, as I have spoken with more and more reloaders that are just getting into reloading or just getting into tinkering I have come to remember that I to was a brand new reloader at one point and as my kids hear me say all the time, “You don’t know what you don’t know”.

Pro Tip: When reloading subsonic rounds use verified data in a reloading manual, I prefer the Hodgdon manual, and slowly make modifications to the load data. This means that you should start with the verified data, shoot a few rounds at that data point and confirm your results match what you are seeing in the reloading manual. It is vitally important that you confirm your data to know if you are in danger. I use the Athlon Optics Rangecraft chronograph. There are other options but ensure you get one like the Rangecraft that is reliable and easily portable.

The proof is in the pudding

When you decided to load subsonic ammo, that is not naturally mean to be subsonic, it is important that you use quality components and take your time. Personally, I like to use Hodgdon Titegroup powder, Hornady Sub-x bullets, Federal primers, and my RCBS single stage press. Now before you jump all over me and start screaming that Titegroup is for pistol, yes you are right. However, we are treading where we are not mean to tread. We are reaching for what is normally out of reach. So, stick with me, like Vegeta said in Dragonball Z (yah we are going there), “YOU SAY I’M ARROGANT, I SAY DAMN RIGHT. THAT’S PRIDE. PRIDE IN THE SAIYAN RELOADER I AM!”.

When you are reloading subsonic 308win the biggest decision you have to make is the weight of your bullet. This decision will determine your powder charge. There isn’t a right or wrong answer on this it simply impacts your powder as you are moving a heavier or lighter bullet.

I like to use the Hornady 190gr SUB-X bullet and I usually start loading Hodgdon Titegroup powder at 8.7gr and then increase or decrease the charge (how much powder) I am using based on the results from my Athlon Optics Rangecraft chronograph. Your goal is to consistently be below 1,125 fps. Personally, I like to go for 1,000 fps so that if I have a hotter round I have a slight window that it could go a little faster and not be supersonic. The other thing to keep in mind is that each firearm is a little different, especially bolt guns compared to semi autos. My Tavor 7, as an example, likes 8.3 to 8.5 grains of Hodgdon Titegroup behind the Hornady 190gr Sub-X round to consistently be subsonic.

Testing and Results

Reloading subsonic 308win was definitely one of those times that I felt, in my soul, a quote from Vegeta (yah we are still there), “I will not stop, I will not rest, until I reach my goal or die trying get really frustrated and take a break”. Subsonic 308win is an abomination to many in the firearms world and it is not something easily achieved as it is not a once size fits all solution. If you are loading for your semi-automatic rifle, in this case our Tavor 7 with IWI 30 cal can, you are balancing trying to make the round as slow but also accurate as you can while at the same time understanding that it is likely not going to cycle the gun. We also have to come to the realization that we are loading unique rounds for the exact gun and suppressor we are testing them in.

A round that is subsonic in my Tavor 7 might be supersonic in my Ruger Precision Rifle. The reliability of subsonic rounds in a semi-automatic can also be far more difficult to obtain. When I load subsonic 308win I put all of the rounds I loaded for, let’s say my Tavor 7, in a Berry’s ammo box and label it with all the specific load data AND what firearm it was for. It sounds overkill but there not many things as embarrassing in the reloading world as going out to show off your subsonic ammo and have it supersonic in the random gun you brought with you. Well it’s more embarrassing to blow your gun up with your reloads but subsonic rounds being supersonic is pretty darn close.

Don’t be an idiot….or topic of my next article

I cannot stress the need to take your time. Like most of us men slowly convincing women to date/marry us you have to take your time. I have spent hours loading 5 rounds, then increasing the powder charge by the smallest margins and loading 5 more rounds, while at the same time decreasing the powder charge by the smallest margins and loading 5 more rounds. Then heading out to the range and shooting all three loads to see which is better. Then using that data to increase or decrease the charge and repeat the process over again until I find the sweet spot for my specific load.

There is nothing more rewarding than finding that perfect load that works in your gun and recording a video for the ‘Gram to show it off. Actually, the most rewarding thing I have done in my life is marry my wife and raise my children, my wife said I had to say that. So if you are looking for the third most rewarding thing in life go out and starting reloading your subsonic 308win.