RE: I have question about increasing pressure in a 308 load
 

I'm trying to analyze why 2700 is a magic number for you...

Do the factory loads give you outstanding accuracy? If this is the case, then it might make some sense to try to get the velocity somewhat close. in alot of cases, a velocity for a given powder will give you similar accuracy for the same velocity load with with a different powder- or at least give you a starting point for finding an accurate load. Without a chronograph checking your loads and factory loads, you won't be able to find your proverbial rear end with a flashlight, mirror, two hands, and a funnel.

Remember- comparing book values to factory values is still comparing apples to oranges. I have different manuals that list significantly different velocities for the same loads.


I think you are overthinking this. If you start a few grains below the max load and load 3-5 rounds for each increment of .5 gr, I have no doubt you will find a good accurate load for your .308 so long as there is nothing wrong with the rifle. When you find a good accurate load, you can go back to your starting point and work the load down in .5 gr increments also for some low recoil practice/targtet loads.

RE: I have question about increasing pressure in a 308 load
 

This does't make sense to me. I have yet to see .2gr make that huge of a pressure difference. I know its a steep waterfall curve with pressure after you lock up brass in the chamber, but I think .2gr is picking pepper out of fly crap if you not using this rifle for competition. I mean the .2gr pressure difference could be alot of things like a fouled barrel. I would try the same workup shooting the 45.7gr first, and then the 45.5gr.

In all my years I have never worked up a load with such fine granularity. Most hunting rifles and weather varible will not let you see the difference in groups. At most I will find out that I have great accuracy between 45 and 46gr and maybe next time I go, I will try 45.5gr and see the difference. If none out of 4 3shot groups, then I always go with the 46gr. But there is too many varibles in even that. A good dynamic load shouldn't matter so much as 45gr and 46gr. Especially with a 308win. A sensitive load maybe.

RE: I have question about increasing pressure in a 308 load
 

I am wondering the same thing. I have used the 308 with 165gr gamekings for years on deer at close to 2800fps with no problems.

RE: I have question about increasing pressure in a 308 load
 

I think you are right I've been driving my self crazy with this LOL last night I hardly slept thinkin about it. 2700 fps is kinda the magic velocity to me since the factory ammo I shot forever was remington 165 grain BTSP's they had, well according to the packaging muzzle veloc. of 2700 fps but for factory ammo at 100 yards they shot awesome the groups looked like one ragged hole. just at 17 dollars for 20 shots was getting rediculous especially as much as I want to shoot reloading was the only answer. I suppose I am trying base my reloads on the accuracy I experienced with those, and yes I am thinking about it tomuch. what I am gonna do just stick with th 45 grains play with the bullet seating depth see what I get, if nothing I will try something else. My biggest problem I think I am doing is I know in reloading asfar as accuracy is concerned there is alot of trial and error to be worked out before you have a good load, I am trying to work out the problems in my head and its not working.

RE: I have question about increasing pressure in a 308 load
 

yeah I know seemed like pickin pepper from fly crap to me too but I was just following 1mile50's recommendation on working up a load. after doing it his way I figured out it was completely pointless, my deal now is im just trying to find a good powder charge to work with.

RE: I have question about increasing pressure in a 308 load
 

i feel 45 grains is what im gonna use i figure its a good starting point i can go either way back down to 44 or back up to 46. Basically from what I am gathering from you guys is that Ill never know untill I atleast try it. perhaps I was giving it tomuch thought thinking I could create a hunting load with competition precision. get the best of both worlds.

RE: I have question about increasing pressure in a 308 load
 

Not to throw another fly in the ointment, but I have had greatluck with BL-C2 lately. Also been shooting alot with 4064 with TSX's. I also can't leave much alone.

RE: I have question about increasing pressure in a 308 load
 

[quote][Also been shooting alot with 4064 with TSX's/quote]

Yup 4064 and 4895 work really well with the .308 also.

RE: I have question about increasing pressure in a 308 load
 

Are those spherical powders?? I was thinking about trying a spherical powder, i was told they meter better then extruded type powders like varget. is that ture?

alright since the powder charge cat is about killed, I have another question about adjusting bullet seat depth. in the past all I ever loaded was canilured type bullets Id seat it so the canilure was just barely exposed from the mouth then I would use a slight crimp. but now with sierra's Im using no crimp but need to figure out a good seating depth. My starting col will be 2.750 and will work it up to 2.800 what kind of increments should I use? should I go by 100ths or thousandths?

RE: I have question about increasing pressure in a 308 load
 

4895 and 4064 are extruded powders. The IMR versions which I use aren't the easiest to meter, though with practice they aren't a problem. I believe Hodgdon 4064 and 4895 have shorter powder grains and should be easier to meter, but I don't use them.

For COL, you need to measure to see if the bullet comes close to the lands. There are a few different ways to do this, but I won't go into the details- try seating a bullet in a resized (empty) case so that the base of the bullet is .300" deep. chamber the round, if you feel resistance from the bullet hitting the lands in the barrel, reseat the bullet so that it is .308" deep, and try again.

If the bullet touches the lands at either point, you will want to measure how far you can seat the bullet out before it hits- reason to start at .300 is to make sure you have some safety margin instead of starting with a .308 depth. If it still touches with a .308 depth, you can adjust the bullet seating depth so its closer to the lands, though I wouldn't go any closer than .020" unless you have a high qulaity barrel on it that was carefully installed and the chamber was cut very carefully and the freebore in front of the chamber was cut very uniform and square.

If the bullet doesn't touch at either point- seat your bullets to .308" deep, or whatever is the maximum length that will function in your magazine- whichever gives a shorter COL.

Seating bullets shallower than its diameter to get you closer to the rifling won't give you any better results- the possibility of the bullet being knocked off center easily and a lack of neck tension more than destroy any potential accuracy gains.