.300 Win Mag in Thompson Center w/ Accubonds

[Conley]

i am having some problems getting my 300 to group. I am using .180 nosler Accubonds with IMR 4831 at 72 grs. and CCI 250 primers. i cant even get a group at 100 yds. Any suggestions on or about my set up would be greatly appreciated. i would like to set it up for a elk hunt to colorado in october.

 

[DevilDawg]

Try using RL22 and Winchester LR primers. Here is the recipe for my T/C 300 win mag. 73.5 gr's RL22, Winchester LR primer. I seat the bullet .010 off the lands. I'm getting 1/2" groups at 100 meters.

 

[JD338]

Conley,

Welcome to the forum.

Try this load which shoots well under MOA in three different rifles:

300 Win Mag
W-W case
180 gr AB or PT
75.0 grs RL22
Federal GM215M primer

**remember to start low and work up**

Let us know how RL22 works out for you.

JD338

 

[Conley]

About what are the FPS with these loads? i will definitly let you know how these work. thanks all i appreciate it

 

[remingtonman_25_06]

Rack up another one for 75g/ RL-22 w/180g bullet...Worked well for me in several different 300 WM's. Primer is a relative issue, they all go bang. I use Fed 215's in my magnums...Velocity will be 3000-3100fps in 24" bbl's. Accuracy is usually .75" at 100 yards for 3-4 different rifles...

 

[JD338]

3000 fps


JD338

 

[DevilDawg]

3000 fps

 

[Conley]

well here is the report. shooting RL 22 at 74 grs using 180 gr accubonds at 100 yds, the group is still some what erratic, about a 3-4 in group. what would be the over all length of your rounds? my C.O.A.L is 3.420. there just seem to be any consistancy between shots.

 

[YoteSmoker]

With the large groups you are getting, I would suspect there is a problem in the optics/mounts rather than the loads. I ran into this problem with my TC Encore with 7-08 barrel. I thought for sure everything was screwed down/loctited well only to find that my base was not tight due to the screws being too long. Ground them down, tightened everything back up and my groups shrunk right up and was able to work up consistent loads, once I figured out what was going on. Good luck!

 

[old #7]

You need to find a COL for your rifle. sometimes your col can make all the difference, sometimes not. Start out about 10 to 15 thousandths off the lands. Also make sure you allow your barrel to cool between shots.
Make sure you are not flinching. I know when I was developing a load for my 300 winnie I started flinch after about 20 rounds. Take your time.
I have had very good results with RL-22 but, every rifle is different.

 

[DevilDawg]

As others have stated, I think you may have more than a COL problem. Check your rings and base to make sure they are tight. I went to using 4 rings on my 300 Win Mag. You also might want to try using an oversize hinge pin. Many T/C's need a hinge pin .001" to .002" oversize to tighten up groups. Mine did and it made a world of difference

Check out Mike Bellm's web page and store if your serious about shooting a T/C.

http://www.bellmtcs.com/store/index.php?category_id=24

Here is a picture of mine. Note the 4 scope rings.

 

[YoteSmoker]

+1 on the Bellm pin. I went with .001 oversize and that baby is tight! I use an old wood handled/brass muzzleloader bullet starter to knock in or out.

Another thing I did to try to help with accuracy was use plastic washers between the barrel screws and the forend and "free-floated" the barrel with the exception of the contact with two washers.

There's forend sollution that uses a "hanger bar" but I believe will only work with a mating custom barrel by Bullberry.

Anyways, these are just suggestions that should help tighten things up for ya. My 223 shot excellent having done this accurizing but my 7-08 would not which told me it was between that barrel and the scope.

By the way, hows the kick on that 300? I imagine it would be quite stout without a break. Maybe something else to consider...

 

[Conley]

well guys after alot of loading and shooting i think i found the sweet spot. 76 gr. of RL 22 with 180 gr Accubonds, CCI 250 primers and a C.O.A.L. of 3.420. I got a clover leaf 1 in. high at 100 yds.

 

[JD338]

Perfect!
Thanks for letting us know how you did.

JD338