Not shooting well enough to hit the V-Bull

JBD

JBD

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I finally got my rifle together. A 223 12 FVSS bedded into a boyds thumbhole stock. With a bushnell 4200 6x24x40 in burris rings sitting on a ken farrel base. I am shooting moly coated 75 grain amax over 25.6 grains of Varget. Getting 3050 FPS.
12fvss.jpg


I only had approximatly 25 rounds on hand but I have made the following observations. I am getting approximately 1 MOA groups at 300 Meters. My groups have both horizontal and vertical stringing. The horizontal I can attribute to wind and my lack of ability in reading it, but the vertical means to me a poor load and or poor loading technique. Or alternatively the rifle does not shoot in the 2s like everybody elses stevens 200 with the sporter contour barrel.:rolleyes:

I am using a lee powder drop if that helps. Any suggestions on how to tighten this up a bit. I am under the impression that I need a mechanical accuracy of atleast .5 MOA to enjoy f-class. I am afraid that goal may be beyond the rifle's capability and mine as a shooter and a reloader.
 
I can't help you with the horizontal stringing, but the vertical stringing may be helped by this:

1 - Set your Lee 'drop' to about 0.2 grains less than your final charge.

2 - Zero your scale with its pan on it.

3 - Drop a "light" charge into the pan, using the powder measure.

4 - Use a powder trickler to bring it up to EXACTLY the right charge weight.

5 - Load it into a case, seat bullet, go shoot.

Powder 'drops' (volumetric measures) are not typically F-class/benchrest accurate. If you're looking for every bit of vertical precision, individually weighing is a fate you'll have to suffer.

If you're really serious, get an electronic trickler like the Lyman DPS systems.

-M
 
Also, if you have access to a longer range than 300 (to help magnify differences) you can test different velocities to find a barrel "node" and reduce stringing even further. You can do it at 300, but it's just harder to see.

-M
 
What do you use as a support at the rear of the rifle. Are you pushing forward on the bipod? Have you tried factory match ammo to see what the base line accuracy is? It looks like a very nice set up that you have now and I would really expect sub 1/2 moa at 100 with that deal as a minimum;)
 
I am using a rear leather bag with bunny ears filled with sand. I was actually shooting off bags today and not off the bipod. Thanks for mentioning the powder trickling loading technique. I have never done that before but it looks like will give me a more precise charge weight then my volume measure. As for getting a base line with match quality ammo that is not really a viable option as I live in Rural New Brunswick, we can not even buy cheap 223 ammo locally much less match grade.
 
Wolverine Supply can ship Federal Gold Metal Match(I know they have 308 175 gr in stock;) and would expect a good selection of 223 as well). If you are using bags front and rear it should take a lot of the movement out of the game too. Might pay to wait for a low wind day for the load development.
 
The groups "in the 2s" shot here with the stevens 200s are actually 1 shot groups, don't go by that, either that or they meant 2" at 100.
 
I'm a novice in precision shooting, but I was able to *consistently* get 0.6 MOA groups at 100 m with my old 223 Rem Savage 12 BLVSS. I sold it a while back, but I'm getting back into precision shooting with a new 223 Rem Savage 16 weather warrior. My favorite projectile is the 69 SMK.

I agree with the weighing every charge by scale comment above. Additionally, that seems like a fairly hot load for a 75 gr bullet. Checking here:
http://data.hodgdon.com/main_menu.asp
I see that a 75 gr bullet with Varget has a min charge of 22.5 gr and max charge of 25 gr powder. Consider re-evaluating your powder charge. A good technique is to load 10 rounds each of ten different powder charges within the recommended range, and then see which powder charge groups the best.
 
lyman lists 25.6 Max. With the moly coated bullets my primers are not even flattened. I experimented with my lee powder drop. There was like a .3 grain variation with the varget. Much less variation with my cheap surplus stuff. I am going to try and load by weighing each charge.
 
jasonburnsdundee said:
lyman lists 25.6 Max. With the moly coated bullets my primers are not even flattened. I experimented with my lee powder drop. There was like a .3 grain variation with the varget. Much less variation with my cheap surplus stuff. I am going to try and load by weighing each charge.
Click to expand...

There ya go! :)

Especially with extruded powders like Varget, there will be much variation.

Finer ball/flake powders will do better - but measures still lead to variation.

Throwing a short charge, then trickling it up to exact specs, is absolutely the way to go. :dancingbanana:

-M
 
Google "ladder testing" and do some research on the topic. Find an accurate velocity and then tune seating depth.

You need to be careful with charge weights in a 223 case because they don't hold much, and small variations can have big effects. Weigh your charges... the suggestion to volume dump a 90% load and trickle the rest is sound.

I would also suggest shooting at 100 or 200 to load develop. I call BS to those that say load eveloping at 100 is useless. a 1MOA group at 100 is only a 3MOA group at 300 because conditions made it that way. You eliminate many unseen environmental variables shooting at 100. If it aint grouping at 100, it certainly will not group at 300.
 
jasonburnsdundee said:
lyman lists 25.6 Max. With the moly coated bullets my primers are not even flattened.
Click to expand...

Fair enough. But I would still recommend testing different charge weights. With my old 12 BLVSS most of the charge weights gave 1-1.2 MOA groups. It was just the 24.4 grs of varget (with the 69 gr SMK) that gave the consistent 0.6 MOA groups.
 
Your charges are on the hot side and may not suit the barrel. My time with savage or stevens never used more then 24.7gr of varget behind a 75gr Amx in Win cases and a CCI 450 primer. Of course, lots of powder varies as do barrels but the speed your indicating is fast.

Weigh your charges to the same tenth grain. Not +/- 0.1gr. Most balance beam scales and other digi scales are not precise enough.

Watch the runout of your ammo. Standard seating dies may not work well with the longer VLD type profiles.

Work up in 0.1gr powder increments. Yes, 223's can be that fussy. I have more load info on my website.

I load test at 200yds with flags on days with as little wind as possible. I have seen enough great 100yds loads fall apart at longer distances, that I don't bother testing that close.

I set my OAL to fit from the mag and it works just fine with the Amx.

I think if you back down on your loads and watch your powder weights, 1/2 min is not out of the question.

For F class factory div, you will be very competitive. For F TR, it will not be so easy.

Jerry
 
Sort your brass at least by weight (.5 gr for .223). Sorting by volume is better but who has time for that:bangHead:

Everything else has already been said.
 
jasonburnsdundee said:
Or alternatively the rifle does not shoot in the 2s like everybody elses stevens 200 with the sporter contour barrel.:rolleyes:
Click to expand...

Jason,
not everyones. My stevens 200 shot a couple of 2 1/4 inch 5 shot groups @ 300 yards. But Tipically in a 20 shot group there would always be a couple outside of MOA @ 300. Hope this makes you feel better.
 
The one thing I have not seen is the standard deviations for your loads. If the brass is prepped carefully, and the necks are uniformly sized, and you check your charge wts carefully for each cartridge then you should get SD's in the single digits or teens, IF the SD is wide then either your loads are not consistent, or to hot and are erratic, and you will never get good vertical dispersion at 300 yards

All the rest of what has been said is also important, but cannot compensate for a wide range in Mvel's
 
If you have access to a chronograph check to see what your extreme spread is.

Trevor
canadianprecision.com
 
The thingabout moly as well, is you have to ge the pressure up to get it to work the same as an uncoated bullet, so typically the bullets are jammed to the lands to get the same and consistent velocity as with uncoated bullets.
i have not messed with moly for quite a few years now, but if you PM maynard, I'm sure he can give ytu the whole skinny on it.
One thing i do rememeber aout it was I cleaned my gun with solvent while using it - BAD move.....!:eek:
 
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