• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

.308 not grouping

Johnny Crash

ok so I have this rifle I just slapped together with stuff I had. The build is as follows.

Remington 700 action
16.5” Krieger Barrel
Tuned factory X trigger
HS precision stock with aluminum bedding block and also skim bedded and Inletted for the barrel
Remington bottom metal
Vortex Viper 6x24
Badger ordinance 20 MOA rail

So before everyone jumps me, I’m no gunsmith and I also didn’t chop a new Krieger barrel down to 16.5 inches. I got the barrel for free after it was cut Per a customers request then they changed their mind, so my gunsmith had it laying around.

So, I assembled everything, thinking it would be a cool woods rifle. I got everything together and went to shoot today. I went with my default load that I shoot out of my 24” Krieger barreled .308. Thought that would be a good place to start. It’s a pretty hot loaded 168 grain.

Anyway, I sighted the rifle in. Brought it in bore sighting with the bolt out and 2-3 rounds on paper.

After that I went to trying to group with it. I shot 3 groups and nothing pretty at ALL. So I decided to break the rifle down and clean it, considering it’s a brand new barrel.

Second time around, it started to group a little better but this time around I noticed it was a little tough to extract on a few rounds. Shot 3 groups and cleaned it again.

Third time around, it started putting 2 rounds together but sending a flyer low and to the right. It wasn’t the exact same result every time but on almost every group it was sending a flyer some where. The best group I shot all day was just under an inch at 100 yards.

It wasn’t the best rest for me but not bad either. I was shooting off my bi-pod and a sand bag under the rear.

When I got home, I did some investigation and realized my barrel was contacting the stock ever so slightly so I tore it down and inletted the stock a little more.

So as I stated, I’m no smith and I’m fairly new to custom builds. I’m just curious what some of my issues MIGHT be and if I’m aware of what they all might be.

Thanks!
 
Last edited:
A 16" barrel will need a completely different load than a 24" barrel. A load developed in the longer barrel probably has too slow of a burn rate for the short barrel. I load for a short barrel and my best loads are with IMR 3031 (around 40.5 grains) under a 155gr bullet. I also have a good 168gr and 175gr load but I don't have the load data handy.
 
The bedding would be very important which sounds like you found... that can cause flyers.
I am thinking that you may have to try some faster burning powder and do some complete load
work ups for a 16.5 inch barrel...I'm no expert either but is something to consider if it were mine.;):)
 
I am a firm believer in having plenty of space between the stock and barrel when free floating. If youve ever watched a barrel on a slo mo camera you will understand that the barrel whips and vibrates much more than people think. And i also believe that is compounded when using a bipod.

Dont take this personal by any means, but ive personally never been able to get any gun to shoot excellent off of a bipod. I know some people prob have, im just not one of them. The rifle really really bounces too much for my liking off of a bipod. And in order to group well with one, your technique needs to be flawless... just my opinion of course.

Be sure you are using new brass for this rifle to start off with. Ive seen many many loads and groups get ruined by trying to cut corners and use "used" brass thats been fired several times in a different gun.

Also in my opinion with that short of a barrel you're probably going to have to go to a tad bit faster powder burn rate for that particular bullet. I just don't think that the load you have developed for the 24-inch Barrel is going to be the optimum load you need for your 16.5" barrel.

If it was me I would make sure I'm using new brass for this rifle and I would go to a good solid front rest and a good rear sandbag like you're using and start with new load development using something in the burn rate of benchmark. All of this after you correct the bedding/fore end problem.
 
Last edited:
I realize the load is an issue. I don’t have my own reloading equipment. I use my uncle, who is a re-loading addict. So I usually work up my load and let him go to work.

I just didn’t have time to work up a load to see what it liked so I went with my default load just to see how the rifle handled. I have some other loads I’m going to send through it tomorrow and see how it reacts now with the float issue fixed.

I have a few 150 grain loads, a 165 grain load and a 175 I believe, that I’m going to shoot tomorrow and see how it responds. I knew the 24” barrel load wouldn’t be perfect but it’s a hot load and I figured it be a good starting point for such a short barrel.

My main concern was the way it was throwing rounds. I’ve seen sloppy groups but they always seemed to be more sporadic, this seemed to be repeating-ish
 
If i had to guess, i would say first and foremost the flyer is caused by the fore end touching. Secondly id say its the bipod. Like uve stated. Fix the fore end and try again. Dont try to rush into changing to many variables at once. You will want to be able to keep track of what causes what to happen. If that makes sense.
 
Yea we need to know the twist first off. Another thing is youre using a 20moa base with a viper which will be at an extreme adjustment for shooting at 100yds so its probably shifting. Lastly you didnt mention wind flags- a wind shift will pitch em out just like you describe. The advice about the faster powder is the next thing to consider.
 
Dusty Stevens said:
Yea we need to know the twist first off. Another thing is youre using a 20moa base with a viper which will be at an extreme adjustment for shooting at 100yds so its probably shifting. Lastly you didnt mention wind flags- a wind shift will pitch em out just like you describe. The advice about the faster powder is the next thing to consider.
Click to expand...

The 20 MOA base is just what I had so I used it. I know it’s over kill but with this set up it actually put me right about the middle of the adjustment range on the scope, oddly.
 
Seat the bullets out close to the lands which will probably be longer than magazine length if it's a short action. You can go in from there.
 
With knowing very little about you or the rifle the barrel contact with the stock could easily be it. The ever so slight contact will definitely cause you grief especially off a bi pod, with varying stock pressure and technique it can be all over the place.
The HS stock will flex so make sure there is enough clearance because when you are on the pod it can force contact and under recoil it can contact.

I would eliminate that first then move on to load development or at least try a box of FGMM and Black hills. Without knowing anything about your shooting (no insult intended) can you shoot well enough off a pod and sand bag to do load development?

My 16.5" 223 in an HS stock took a little technique tweaking off the pod but shot like a hammer once i figured it out. Load development off a rest and firm hard hold off a pod and things worked fine.
 
Drop Port said:
With knowing very little about you or the rifle the barrel contact with the stock could easily be it. The ever so slight contact will definitely cause you grief especially off a bi pod, with varying stock pressure and technique it can be all over the place.
The HS stock will flex so make sure there is enough clearance because when you are on the pod it can force contact and under recoil it can contact.

I would eliminate that first then move on to load development or at least try a box of FGMM and Black hills. Without knowing anything about your shooting (no insult intended) can you shoot well enough off a pod and sand bag to do load development?

My 16.5" 223 in an HS stock took a little technique tweaking off the pod but shot like a hammer once i figured it out. Load development off a rest and firm hard hold off a pod and things worked fine.
Click to expand...
This is exactly what I would. ^^
(You can't build a house with out a foundation.)
 
Do you want a hunting or a target gun one inch at a 100 yds is not bad for a hunting gun clean up the stock and work up a load and you will do better
 
You must log in or register to reply here.

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Classified Ads

Forum statistics

Threads
165,242
Messages
2,192,005
Members
78,771
Latest member
AndrewL

Share This Page

Back
Top