Please help me with my .204 Group

[wildcat284]

Hey guys,

Took my Kimber Pro Varmint to the range yesterday with a variety of loads. I shot this group, but as you can see the shot dispersion of the 3rd 4th & 5th shots is way over to the left of the first 2. Each of the squares is 1/2 inch.

The load on the target shown below was 29.8grs BLC-2, 39gr Sierra Blitzking, Federal 205 primer. Case was Sellier & Bellot. OAL of the load was 2.280, which is the maximum to fit in the magazine box.

I shot 29.8, 29.9 and 30.0grs, and in each case the groups had a similiar shot dispersion - the first 2 through virtually the same hole and the other 3 were over to the left. The 29.8 gr load however had the less shot dispersion.

My runout was apalling to say the least, have now corrected the problem,set up of die). What else could be the cause of a group like this?

I should also mention that this is a brand new rifle, I have put 90 rounds down the barrel, so maybe still running in?

All replies to this will be greatly appreciated.

Regards,

Michael.

 

[82boy]

There is a lot of variables that can cause problems such as this. The first thing that comes to mind, are you firing the shots in the same conditions, i.e. no changing winds.

Could be the components maybe the barrel don’t like the bullets your using. Could be an ignition problem try different powders, blc2 is a ball powder and is harder to light, perhaps the primer may also be problem. what was your run out problem you corrected, and how did you correct it? So try different bullets, powder, primers, and brass.

Last may be something to do with the barrel cleaning process, I found the 204 to be picky with cleaning. My 204 don’t like to be cleaned, it shoots bad when you do, it will shoot 5 shoot 100 yard groups in the .3 area all day long until I clean it. The gun even shoot like this when it was so dirty it would key hole rounds every once in a while, in that case I had to clean it, to stop the key holing problem. Then it shot like crap until it got a few rounds dirtying up the tube.

 

[82boy]

Something that I just tought of, and usualy is the first thing I would look at with accuracy problems, the scope. Do you know for sure the scope is good, just because it is new dont mean it is right. Check it with a second scope, this may fix your problems.

 

[wildcat284]

The runout problem was caused by my shell holder,Lee), not having the case in alignment with the seating sleeve on my Hornady New Dimension Die. So the case mouth would catch on the mouth of seating stem, causing the case to go in crooked, then when the bullet was seated it would bend the neck. The majority of my cases had runouts greater than .010. Of course, those cases came right after fireforming, I noticed that once fired brass exibited runouts of between .000 and .001.

I am just waiting on a new shell holder, so in the meantime I'm part running the cases into the seating die sleeve, then lowering the press ram, which then causes the case to be in perfect alignment. All this I figured out after firing all my reloads. However, I'm due for an all day range session on Friday so i'll be set this time. Taking my scales, press & gear to the range so I can load whilst I'm there.

I fired some Hornady factory .204, interesting that the groups printed on my target in a similiar pattern as my reloads. My rifle liked the Sellier & Bellot 32gr factory, the groups were not spread out like the Hornady or my reloads, and the groups hovered around the 1/2 to 3/4 MOA.

I also brough 1lb of H4895 today so I'm going to try both this and my BLC-2 to see if that helps in the accuracy.

Regards,

Michael.

 

[Bench4fun]

Ya', it sounds like that there are too many variables that come into mind when you think about it. One that comes to mind is also trigger pull. Do you know that pulling the trigger can effect your accuracy by atleast an inch? So it's CRUCIAL that you squeeze the trigger the same every time,or touch everytime if you have a top-of-the-line 1 oz. trigger like my cousin). Also the winds and even the temperature can be a crucial variable. So if I were to give out any advice for in the future it would be this: Try to go out on a calm moderately warm day where there is little or 0 wind.

 

[wildcat284]

Hi, thanks guys so far for your input.

Trigger - yes that was the first thing I adjusted, as the pull was 3.5 lbs, so I lightened it off to just under 2 lbs. The trigger on this Kimber is excellent, crisp, smooth and consistent, and breaks like glass. I have taught myself trigger control by dry firing on the kitchen table. I now have it down to the point where the cross hairs in my scope do not move at all when i squeeze the trigger.

I am just loading up some ammunition with H4895, as well as BLC2. I also checked the bedding and locking lug alignment, all as it should be in that department.

I am narrowing the cause of the group down to the barrel still needing a few more shots down as it may still be in the running in process,I know a guy with one of these Kimbers, who said it took between 100 & 200 rounds before his barrel settled in), plus the awful runout on my previous handloads, which as stated above I have now solved. I will have a good idea where I am going after Friday.

Regards,

Michael.

 

[Bkluke]

accurate 2015 works real good with the 39gr pill for me 25.6 grains with rem 7.5 primers. it could be as 82boy said, that the barrel does shoot well, when it is clean, my sako is the same way, my sako took about 35-40 rounds down the tube before it started to shine. don't give up though, this is a very accurate cartrige.

 

[vmthtr]

Something no one mentioned yet is barrel clearance. If the barrel is touching the stock, when heated it can walk the group around.

Mike

 

[OpossumMcMuffin]

Hey Michael,

I've just finished my load development for my 204 Cooper model 21 and what turned out to work the very best was 27 grains of IMR 4064 which is not listed as an accuracy powder that I know of but my Cooper is shooting between .4 & .5 @100 with the 39 grain blitzking seated .010 back from the lands.

Fed 205M primers but I'm going to try CCI match tomorrow.

 

[GoneBallistic]

The list of things that could be affecting your accuracy is almost limitless. I advise people to make a written list and start eliminating them one by one. Here's a partial list of possibilities:

1. Wrong bullet/powder combination for the barrel.
2. Poor or wrong cleaning regiment for your barrel.
3. Faulty scope/reticle/rings or loose mount.
4. Barrel with pressure points on the stock - may be good or bad.
5. Action may need bedding.
6. As you said, shells with too much run-out.
7. Bad range/shooting conditions,wind).
8. Wrong bullet weight for the barrel twist.,try lighter bullet)
9. The .204 wants thick primers when near max. loads,CCI,Fed. Rem. only)
10. Poor bolt/chamber alignment.
11. Rough barrel/bore,not likely on the Kimber but possible).
12. Poor trigger control or shooting technique.

I'm not saying that you're doing some or all of these but until you eliminate them one at a time,for sure), they'll all mess with your groups.