subsonic 308 load


That is my website. :)

The data and info there came from several years of experimenting with a variety of different subsonic loadings and bullets in a couple of different cartridges.

I keep hearing about detonations, but propellant powder can't detonate if we adhere to the definition of the word, which indicates the presence of a shock wave.

Actually it can. Some powders, especially the older brands, contain nitrogylcerin. If the powder is not properly ignited, it can smoulder and release the introglycerin as a vapour. That can then detonate in a high order explosion and blow even the strongest action to bits.

I have seen two handguns destroyed in this manner. Both had the top of the cylinder and top-strap blown right off by light loads. In both cases the shooter escaped with only a scare but this kind of event has the potential to be very dangerous.
 
Anyone have any subsonic load data for 308? I have Wchstr lrg primer, IMR trail Boss and Hndy 168 grn projectiles.

Depending on the twist rate the 168gr bullets may not stabilize at low velocity. That weight always gave me the most trouble, I think because the bullets are inherently poorly balanced.

It is VERY important to lube subsonic bullets to prevent sticking them in the bore. This can and will happen if you don't lube. If you don't pay attention to each shot to ensure the bullet leaves the bore it is more than possible to put a second round down the bore with predictable results.

If you don't take my warnings seriously, consider this picture. This is one of the two bullets that I personally stuck in a rifle bore. :mad: It was embarrassing but I was paying attention and didn't send a second round after it.

BulletStuckinBore.jpg
 
Depending on the twist rate the 168gr bullets may not stabilize at low velocity. That weight always gave me the most trouble, I
I



think because the bullets are inherently poorly balanced.

It is VERY important to lube subsonic bullets to prevent sticking them in the bore. This can and will happen if you don't lube. If you don't pay attention to each shot to ensure the bullet leaves the bore it is more than possible to put a second round down the bore with predictable results.

If you don't take my warnings seriously, consider this picture. This is one of the two bullets that I personally stuck in a rifle bore. :mad: It was embarrassing but I was paying attention and didn't send a second round after it.

BulletStuckinBore.jpg


appreciate all of the great advice I am getting here, and especially the warnings. I will look for a heavier projectile, and start a little higher in the grain count for powder and work backwards. Next question I am new to this and have already loaded a few rounds with 9.5 and 10 grains, what is the safest way to remove the projectiles and powder then remove the live primers? or am I better off just scrapping them?????
 
Depending on the twist rate the 168gr bullets may not stabilize at low velocity. That weight always gave me the most trouble, I think because the bullets are inherently poorly balanced.

It is VERY important to lube subsonic bullets to prevent sticking them in the bore. This can and will happen if you don't lube. If you don't pay attention to each shot to ensure the bullet leaves the bore it is more than possible to put a second round down the bore with predictable results.

If you don't take my warnings seriously, consider this picture. This is one of the two bullets that I personally stuck in a rifle bore. :mad: It was embarrassing but I was paying attention and didn't send a second round after it.

BulletStuckinBore.jpg

Also one of the few benefits of age is patience, I will definately ensure that each round clears the barrel before firing again, that is the really nice thing about the rem 700 bolt action it is easy to remove the bolt when you are not in a hurry, I would rather take my time and get them all on target ;-)
 
Next question I am new to this and have already loaded a few rounds with 9.5 and 10 grains, what is the safest way to remove the projectiles and powder then remove the live primers? or am I better off just scrapping them?????

I would leave them at this point, start higher and work down to that load (assuming you still want to use the bullet/powder combo you have loaded). If you run into problems before that charge weight or want to start over with a new load, then an inertia type or collet puller will let you pull the bullets without mangling them. You don't need to decap the live primers, just pull the decapping rod out of your sizing die, re-size them and then load whatever bullet/powder you end up using.

Mark
 
Winchester 785 powder was my favourite for reloading my .270 Win, the problem was it was short lived and discontinued due to detonation problems when used below the recommended starting load.

wwwarning.jpg


wwcat.jpg


Its hard to see but 785 powder below has a *asterisk* by "ALL" its load data.

ww785.jpg
 
I would leave them at this point, start higher and work down to that load (assuming you still want to use the bullet/powder combo you have loaded). If you run into problems before that charge weight or want to start over with a new load, then an inertia type or collet puller will let you pull the bullets without mangling them. You don't need to decap the live primers, just pull the decapping rod out of your sizing die, re-size them and then load whatever bullet/powder you end up using.

Mark

Thanks, I was thinking of removing the primers to enlarge the flash holes to 9/64, but if there is no safe way of doing this i will leave as is for now.
 
Accurate Arms #9 is a good powder for subsonic loads among others, it would be harder to stick a cast bullet in the bore, and if by chance you did, it would be easier to push out. All my subsonic testing was done with a .300 Whisper and cast bullets, accuracy was not up to the same level as higher velocity loads, I believe it was because of twist/stability problems.
 
Thanks, I was thinking of removing the primers to enlarge the flash holes to 9/64, but if there is no safe way of doing this i will leave as is for now.

Push the primers out with your regular decapping pin, just use a gentle push and you can re-use them.
And for pulling the bullets, if you just have a few, a kinetic (hammer-type) puller is fine; but if you've built a bunch, you're better-off getting a collet-type puller (I've read and heard nice things about the Hornady "cam-lock" puller; but my old Forrster works just fine.
 
Anyone have any subsonic load data for 308? I have Wchstr lrg primer, IMR trail Boss and Hndy 168 grn projectiles.

I am thinking of trying 95. grains and working up from there

You haven't really told us anything about the rifle you're planning on using. More info on barrel length and twist rate would be a big help.

There are a lot of guys shooting 180 gr. RN bullets with Trail Boss that are having accurate and reliable perfprmance in 1/12 barrels using around 10.0 gr. of powder. Modifying flash holes is a pain in the ass and not necessary with Trail Boss.

Best accuracy in .308 subs appear to come from barrels 20" or less in length.
 
Thanks, I was thinking of removing the primers to enlarge the flash holes to 9/64, but if there is no safe way of doing this i will leave as is for now.

I didn't mean to give you the impression that decapping live primers is unsafe, I just mentioned that you can re-size without decapping to save you a step. If you want to decap the live primers, go ahead. Just use a gentle, smooth motion on the handle. As with all reloading, safety glasses are highly recommended.

Mark
 
Next week's will probably be "wandering zero" or....

I would hate to have to try to even estimate how many "plinking" loads I've fired in my 30-30's, using 5 gr. 700X and a 93 gr. Lee moulded WW bullet. I have fired a pile of 10-12 gr. 700X with 150+- gr. WW Lee moulded bullets as well, in 308, 30-06, 8mm, etc.

Mr. kjohn, oodles of us did these things for many years. I used every powder I could think of for light loads with cast bullets in the 30-06. For heavier cast loadings I found H4831, at about two-thirds a case full, to be one of my most accurate loadings. Now I hear where these fellers who have learned so much from their books, say a light load of H4831 will make my rifle "blow up in my face."
However, in the old days nothing bad like that ever happened, we just did our thing as common sense told us it should be done. Then it all changed. And the change came when a light load was no longer a light load, or a plinker load, it suddenly became a sub sonic load, and the rules all changed. This sub sonic load had to be assembled just so, in strict accordance with someones idea of how a sub sonic load should be loaded. Don't do it any different, or your gun might blow up in your face!
Hard on the heels of sub sonic came this spill over thing. I new about spill over for a long time, but my version was spilling the powder in getting it back in the can. In the new version them fellers tell me it might blow my gun up!
I've said it before. Many newer reloaders spend far too much time in reading some guys version of a theory that will somehow cause us harm, like blowing our rifles up.
Kjohn, how can I get it across that we used to have fun reloading and trying different ideas and we were not worried stiff about our guns blowing up?
 
You haven't really told us anything about the rifle you're planning on using. More info on barrel length and twist rate would be a big help.

There are a lot of guys shooting 180 gr. RN bullets with Trail Boss that are having accurate and reliable perfprmance in 1/12 barrels using around 10.0 gr. of powder. Modifying flash holes is a pain in the ass and not necessary with Trail Boss.

Best accuracy in .308 subs appear to come from barrels 20" or less in length.

A bit about the Rifle and optics.

REM 700 with Sako extractor.Accurized(squared) action(308)

Pac Nor Select match , 30 in ,Palma profile,1/13 twist for 155 Gr ammo,Stainless.243 rds into it that’s it

Accuracy International 1.5 Green stock.

Farrell 20 MOA base

Leupold MK4 Tactical scope 4.5 X14 X50mm Duplex with Badger rings
 
Lapua makes special .308 200 gran bullets for this application.

This is prob the best subsonic bullet I ever tried. They are accurate and easy to stabilize.

I was thinking of removing the primers to enlarge the flash holes to 9/64, but if there is no safe way of doing this i will leave as is for now.

You should also use Mag primers to ensure proper and complete ignition of small charges of pistol powders.

Make sure you mark the cases with the drilled flash holes cause they won't be safe for full power loads. I took to bluing the case rim cause it was easy to do and easy to see.

BlueRim-small.jpg


Trailboss is easier to work with because it is so fluffy and will give better load density.
 
Twist is slow for a heavy bullet at low velocity. use a round nose bullet to shorten the bullet.

Making flash hole bigger will make ignition wose. The smaller the hole the better. I use berdan for subsonic. Very small holes.
 
in the old days nothing bad like that ever happened, we just did our thing as common sense told us it should be done. Then it all changed. And the change came when a light load was no longer a light load, or a plinker load, it suddenly became a sub sonic load, and the rules all changed. This sub sonic load had to be assembled just so, in strict accordance with someones idea of how a sub sonic load should be loaded. Don't do it any different, or your gun might blow up in your face!

Well we used to play chicken with lawn darts and smoke in front of our kids and drink when pregnant but then we learned better. Just cause you did it 10000 times and never had a problem doesn't mean there wasn't the potential to kill yourself. Dale Earnhart refused to wear a head restraint cause he claimed that no crash had ever killed him. Then he died in a crash from a basal skull fracture that could have been prevented with a $5 head restraint. Nowdays all Nascar drivers wear head restraints. We can learn and improve and hopefully it doesn't take someone dieing to make us do it.

I have personally inspected two handguns that had exploded from light loads. In those cases the gun is being held away from the face and head and the explosion on a wheelgun tends to be directed upwards. A rifle is a different case. The shooter's head is directly behind the bolt and depending on how it is being held, the meat of the upper arm with the large brachial artery is very near to the barrel-action joint. A sliver of shrapnel in the wrong place and you will die before the ambulance can be called.

If you want to ignor safety and risk your life, then you are free to do so. However to counsel others to ignor basic safety precautions is reckless and wrong.
 
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