Help with 20VT

[Bigguy1951]

I love my 20VT but I can't seem to solve one problem, extreme spread. I have used Acc 2200, LT-32 and CFE Blk, 32gr, 39gr and 40 gr bullets and three different neck bushings, the smallest 226, and cannot get the ES below 40 and it can go over 70 on some loads. My brass is all LC-04 and was neck turned to 0.0125 as I have a 0.232 neck. The little gun is incredible at 100 yds but at 200 yds the groups are opening up and at 300 it is pot luck with groups running around 1/2 moa or slightly larger. Any help would certainly be appreciated.

 

[K9TXS]

What twist barrel?

 

[jds holler]

Hmmm.. I don't think you've got much to bitch about. If you're still at 1/2 MOA at 300 yards, with those little pills, you're doing pretty good in my book. jd

 

[Bigguy1951]

The barrel is 10 twist I believe. I will have to check to be sure. The problem JD is that a group can blow up because of the ES. Today in a club competition my 200 yd group was almost as large as my 300 yd group, 1.116.

 

[Bigguy1951]

What twist barrel?

Definitely a 10 twist

 

[Gabe22BR]

Depending on how quick it warms up in testing- barrel & ambient temperature
Them ball powders aren’t very stable
I have moved away from them, changed to stick powder..just my experience..

Annealing helps with neck consistency , I use a .230 on my 20VT & .229 on my 20-221AI

 

[Evan]

X-Terminator is the most stable ball powder I tried in mine and it was still sub-par. Imr 4198, H4198, Benchmark, and IMR-3031 all worked well, although it was hard to get enough 3031 in the case. I think you need to check your ignition system too. From firing pin spring, to pin fall, to protrusion, to primer, to how you’re seating them. My 20VT, with 55gn Bergers, groups under 2 inches at 600 yards. This case is capable of adequate ES.

 

[chuckshooter]

what primer?

 

[S&sprecisionTx]

I second the annealing and I would definitely check the neck thickness to your chamber is proper clearance

 

[linebaugh]

Your groups do not seem bad if the environmentals are anything other than good to very good. I seldom use ball powder but 40 +ES seems doable with ball powder. I run H4198 in mine with 39/40gr bullets. You might want to give a different powder a try or see if you have neck clearance issues. Its been a cpl years since i built mine but it seems like there were two camps on the reamers and they were evenly split from no turn and turned necks. Or perhaps I am remembering wrong on the turning. Perhaps it was brass neck thickness and reamers per brand of brass?? Either way I wonder if this is part of the issue.

 

[Bigguy1951]

Depending on how quick it warms up in testing- barrel & ambient temperature
Them ball powders aren’t very stable
I have moved away from them, changed to stick powder..just my experience..

Annealing helps with neck consistency , I use a .230 on my 20VT & .229 on my 20-221AI

I anneal every firing.

 

[Bigguy1951]

what primer?

I have used federal 205, CCI BR-4, CCI 450's, Win #41 and CCI #41 without improvement.

Your groups do not seem bad if the environmentals are anything other than good to very good. I seldom use ball powder but 40 +ES seems doable with ball powder. I run H4198 in mine with 39/40gr bullets. You might want to give a different powder a try or see if you have neck clearance issues. Its been a cpl years since i built mine but it seems like there were two camps on the reamers and they were evenly split from no turn and turned necks. Or perhaps I am remembering wrong on the turning. Perhaps it was brass neck thickness and reamers per brand of brass?? Either way I wonder if this is part of the issue.

There are still two different neck styles. The "Lapua" neck which is larger so that brass does not need to be trimmed and the 0.232 neck that does require the brass necks to be trimmed. I have the later.

 

[Gabe22BR]

Only change 1 thing at a time, all I can say…
all I can do from here… w/o seeing or watching you prep/ load/ shoot…

 

[L.Sherm]

Get some Rem 7.5

 

[17VLD]

I am curious about the one variable not yet mentioned, case volume. It would be pretty easy to weigh a few cases until you come up with 5 that are the same exact weight and then if you could try some Berger 40s with some VV130 you would probably see a decrease in s.d. It might be fun to keep those 5 cases segregated and load at the range if possible and you may be very surprised at how well your gun shoots. Don’t beat yourself up to much, small cases are sometimes tough to get s.d.’s down. I can think of a certain 17 Mach1V that gave me fits but shot extremely well at distance. I mentioned the 40 Berger because it is my go to 20 caliber bullet to check extreme accuracy in my rifles.Of course your rifle will be different.I am sure if we could still get Lapua 221 brass this conversation probably wouldn’t be taking place
Matt

 

[Evan]

I am curious about the one variable not yet mentioned, case volume. It would be pretty easy to weigh a few cases until you come up with 5 that are the same exact weight and then if you could try some Berger 40s with some VV130 you would probably see a decrease in s.d. It might be fun to keep those 5 cases segregated and load at the range if possible and you may be very surprised at how well your gun shoots. Don’t beat yourself up to much, small cases are sometimes tough to get s.d.’s down. I can think of a certain 17 Mach1V that gave me fits but shot extremely well at distance. I mentioned the 40 Berger because it is my go to 20 caliber bullet to check extreme accuracy in my rifles.Of course your rifle will be different.I am sure if we could still get Lapua 221 brass this conversation probably wouldn’t be taking place
Matt

Thats a great point. I have Lapua brass that I’ve sorted by volume.

Another thing to check in your ignition system in firing pin drag. Quick test is how do repeated dry fires sound. If the noise changes, the pin is dragging somewhere and that will cause erratic ignition.

 

[chuckshooter]

I have found an expanding mandrel can take a lot of guess work out of neck tension. also recommend full length sizing, incase you are not. these kinds of post are difficult to respond to without more info in the first post. often people are recommending things to try, only to be shot down by a response of, I already do that or I have tried that. so, that's why you will get a lot of shotgun answers. also what barrel? action? it has already been said, are you maybe expecting more than this is capable of? benchrest versus varmint accuracy? I reload for 6 vartargs, when I go on a trip, there is always 2 or more of them in the truck, they are great critter killing machines but, I have never put mine on paper at 300 yards,

 

[Bigguy1951]

Only change 1 thing at a time, all I can say…
all I can do from here… w/o seeing or watching you prep/ load/ shoot…

Thank you, but I always check changes 1 at a time. The exception is primers where I loaded up all the previously mentioned primers and tested them all in one day.

I am curious about the one variable not yet mentioned, case volume. It would be pretty easy to weigh a few cases until you come up with 5 that are the same exact weight and then if you could try some Berger 40s with some VV130 you would probably see a decrease in s.d. It might be fun to keep those 5 cases segregated and load at the range if possible and you may be very surprised at how well your gun shoots. Don’t beat yourself up to much, small cases are sometimes tough to get s.d.’s down. I can think of a certain 17 Mach1V that gave me fits but shot extremely well at distance. I mentioned the 40 Berger because it is my go to 20 caliber bullet to check extreme accuracy in my rifles.Of course your rifle will be different.I am sure if we could still get Lapua 221 brass this conversation probably wouldn’t be taking place
Matt

Matt the capacity has been the one thing that was most on my mind. I used only 1 year of LC brass to help control that and also weighed each piece and threw out the outliers. The 200 pieces of brass I have are all within 2.7 grains. I would prefer it if it was less. I will try your 5 case suggestion though. Small differences have a big effect on small cases.

Ignition timing is a possibility. The firing spring on the gun has not been replaced in just over 2 years. I have ordered 2 new springs and will test them when they arrive. I have listened for drag and could not hear anything. I disassembled the bolt and it is clean and there are no obvious signs of drag.

I have found an expanding mandrel can take a lot of guess work out of neck tension. also recommend full length sizing, incase you are not. these kinds of post are difficult to respond to without more info in the first post. often people are recommending things to try, only to be shot down by a response of, I already do that or I have tried that. so, that's why you will get a lot of shotgun answers. also what barrel? action? it has already been said, are you maybe expecting more than this is capable of? benchrest versus varmint accuracy? I reload for 6 vartargs, when I go on a trip, there is always 2 or more of them in the truck, they are great critter killing machines but, I have never put mine on paper at 300 yards,

Chuckshooter every reply is valuable and appreciated as it may well be something I have overlooked. I use or have used expanding mandrels on my 22-250, 6BRA, 6.5x55, .243,.and 300WM. I have not used them here as I am not at a fine tuning point yet. I use a Redding full length bushing die to resize. I don't think I am expecting too much from this cartridge based on the many comments in other threads that I have read. The action is a Savage Model 12 and the barrel is a Shilen stainless select match. I am pursuing this because I enjoy trying to find out how well I can make a gun shoot.

I am trying to locate some N130 locally to test. Shipping and hazmat on a single pound make it hard to swallow and avoidable if at all possible. Natchez has a great deal right now on 8lbs of the N130, $270. Lowest price per pound I have found anywhere. None of the other mentioned powders are available locally as well.

Berger 20 cal bullets and Lapua 221 brass seem to be on the same shelf right now. Berger is my go to bullet regardless of caliber but I have not seen any to buy.

 

[L.Sherm]

If you are going to try Viht powder go with 120

 

[JSH]

I was happy with mine until this post.
Small cases, small to minute changes can make a huge difference.
@ 300 it could very well be a condition change.