Thread: Better accuracy for my 308

Hi Knowledgeable people,

Ive currently acquired a 308 and through these difficult times acquired powder, unfortunately I can only get my hand on 150sst (which I do enjoy shooting) so these are what I have to work with.

Down to the range! 9x rounds of 2206H at 42g,43g,44g with the SST seated 10thou of the lands. I usually do my ladder test at .5 increments but with the shortage of powder I decided not to.

The best group I got was 1inch group at 43g.

My question is if this was you what would be your next step? Bullet change? powder weight/brand change? seating depth change?

cheers

Load up 20 and go hunting. 1” at 100 will be accurate enough out to 300yds or so if taking shoulder shots on deer.

Id load .3gr either side to see if your near a stable node. Vertical generally is powder charge, horizontal is often seating depth. 1gr increments are quite big in a medium capacity case like 308. I do .5 in long magnums and .3 in 308, 6.5cm, 243 etc size cases.

A 100 metre group under 2 MOA is perfectly acceptable for hunting. 1 MOA or better is target shooting territory!

Absolutely it is.
If you wanted to play with seating depth that may increase the accuracy, or not. Either way 1” is as good as most rifles/ person combination get.

What’s of more consequence is the first cold shot consistency.

Greetings Stefanhope,
I read through your post and responces to date, most of which suggested you load up a batch and go hunting or words to that effect. This is good practical advice. Long ago I was advised to just use the middle load or half way between start and max. I looked up some of my earliest load manuals and found that the middle load for 150 grain boat tail or flat base projectiles was 43 grains of IMR4895, a very similar powder to H4895/AR2206H.
So you have a good load, perhaps not the best load but a good one none the less. Proper load testing takes a lot of time and a lot of components with the latter currently in short supply so if you want to go down the load testing and development route you may wish to consider the following. First load up a batch of the 43 grain load, get your rifle properly zeroed for them and use them for hunting from now to mid winter. Accuracy is made up from three components, the load, the rifle and the shooter. The last is likely the most important. My testing is done on my home bench using a front padded adjustable rest and a rear bag. Even with this a rock solid rifle position, the fore end held down a clean trigger release is needed for the best results. The rifle needs to be properly bedded and the scope rings and bases tight. Lastly one three shot group tells you little about the accuracy of the load as a really tight one can just be chance. Additionally the .308 is a very easy rifle to load for so most loads shoot quite well.
So Stefanhope it is your choice how far down the load development rabbit hole you go. There are no bad choices. Just make sure you always have your rifle zeroed for your current load so you can always go hunting with it.
Regards Grandpamac.

Originally Posted by Stefanhope

Hi Knowledgeable people,

Ive currently acquired a 308 and through these difficult times acquired powder, unfortunately I can only get my hand on 150sst (which I do enjoy shooting) so these are what I have to work with.

Down to the range! 9x rounds of 2206H at 42g,43g,44g with the SST seated 10thou of the lands. I usually do my ladder test at .5 increments but with the shortage of powder I decided not to.

The best group I got was 1inch group at 43g.

My question is if this was you what would be your next step? Bullet change? powder weight/brand change? seating depth change?

cheers

Whats your benchmark for accuracy with this particular rifle. This may already be the best it is capable of.

One inch,dont waste any more time or ammo at the range.Go hunting as Stug said.
Six deer this summer didnt like my 308 tika shooting 150ssts.I dont reload,just zero at a hundy and shot deer.

Yes, as zeropak says, really depends on the rifle. Should the rifle be capable of better? If it's an old BSA or something then 1MOA is great, quit whilst you're ahead and go hunting. If you've got a new Sako and really want to extract the most out of it...

A mate of mine reliably gets cloverleaf groups with the 165 SST but has struggled recently with the 150's. They aren't the most consistent bullets so the accuracy potential might be a bit limited. I suggest backing them away from the rifling a lot more, giving them maybe 50 or 60 thou jump and seeing how that compares. The thinking here is:

A) They are not a VLD style bullet that should need to be snug against the rifling.
B) If they are a bit inconsistent, giving a lot more jump means they'll all end up with a good amount. Up close, some might end up with very little, and others might have twice as much and that's asking for flyers.

1gr steps are also really broad and you might have skipped over a point where the load might shoot a lot better. If you have access to a chrono, there are some tricks you can use to try and shortcut the process and cut down on the components used.

You got a photo of your spent brass with carbon still on the necks? Maybe pop up a good pic so we can see if you've got a consistant burn pattern. Also a pic of the
Primer strikes? Good to check if you have pressure signs (my accuracy nodes are never too warm)
Quick question, did you use a modified case and gauge to check distance to the lands or just the feel of the bolt?