75VLD vs 80VLD in 223 8 twist

[DBLNUT]

I have been shooting a 8 twist 223 out to 500 yds with the Berger 80's but recently saw on their web page where the optimum twist is now changed to 7.5 twist for the 80VLD's. I was thinking maybe the 75's might be better matched to my 8 twist?? Any thoughts on this??

 

[boltman223]

Going by bergers adjusted BC numbers with the marginal stability of an 8 twist for both the 80 and 75 there is very little difference at 500 yds. Thats assuming you get 150fps more with the 75's, I don't know if you'd get that much though. I'd say it's a wash really.

 

[Rtheurer]

Did they not group well? Sometimes when you don't know... You can remain fat dumb and happy and all is right in the world. Now that this twist rate calculator is out ....for some reason my ammo just does not shoot as good as the thousands upon thousands of 80gr 223 ammo I have shot up over the last decade.

So you loose a few points of BC... Big woop. Next barrel put a 1:7twist on the ole gal.

Just my two cents. I will continue to shoot the 80's because they shoot great.

Russel

 

[DBLNUT]

I put 850 rounds of the 80VLD thru it last year, with my best load I will say it averages 1" at 300 and 2.75"-3" at 500 for 5 shot groups, I have had quite a few 2-2.5 and 1-5 shot group that went .875 so it does shoot well with the 80's, just wondering if maybe the 75 might be better.

 

[boltman223]

What's your velocity with the 80's?

I would think that the 80's would beat the 75's, but that's more of an assumption. You'll have to plug the numbers into jbm or something like and see what velocity it would take overcome the BC advantage of the 80.

I'm not sure how fast you csn get with the 75's maybe somebody will post there speeds.

Your accuracy seems pretty good with what you have I don't know if I'd change. Try it and find out for sure

 

[DBLNUT]

I am shooting 24.75 of Varget with a .015 jump, velocity is right at 2920fps. Gun is a Defiance Deviant action with a 26" 8 twist Mullerworks barrel.

I do have 800 of the 75VLD's to try.

 

[manitou210]

I have been shooting a 8 twist 223 out to 500 yds with the Berger 80's but recently saw on their web page where the optimum twist is now changed to 7.5 twist for the 80VLD's. I was thinking maybe the 75's might be better matched to my 8 twist?? Any thoughts on this??

Its actually 1/7 twist for 80 gr vld I would suggest forget about VLD bullets and go to the 80.5 fullbore Target, or long range BT Target 82gr you will have better results with your 1/8 twist barrel.
Berger is slowly stopping product on a lot VLDs,

 

[eric n]

I bet the difference between the two would be lost in the wind given the velocities that are safely achievable with each.
If you are shooting for small groups, the wind will blow it at 300 more then people want to believe. It just gets worse the farther you go and positional errors are amplified as well.
Your groups are nothing to sneeze at, pretty good really depending on your setup (rest, bags, bipod, etc.).

One of the first posts I made on here was responded to with a question... "What is your goal?"
So... what is your goal?

 

[DBLNUT]

I bet the difference between the two would be lost in the wind given the velocities that are safely achievable with each.
If you are shooting for small groups, the wind will blow it at 300 more then people want to believe. It just gets worse the farther you go and positional errors are amplified as well.
Your groups are nothing to sneeze at, pretty good really depending on your setup (rest, bags, bipod, etc.).

One of the first posts I made on here was responded to with a question... "What is your goal?"
So... what is your goal?[/QUO

To average 2" grops at 500

I bet the difference between the two would be lost in the wind given the velocities that are safely achievable with each.
If you are shooting for small groups, the wind will blow it at 300 more then people want to believe. It just gets worse the farther you go and positional errors are amplified as well.
Your groups are nothing to sneeze at, pretty good really depending on your setup (rest, bags, bipod, etc.).

One of the first posts I made on here was responded to with a question... "What is your goal?"
So... what is your goal?

My goal was to try and keep even with the 2 guys shooting 6BR's at our local match, I was only trailing them by 1-2 points over the last 4 shoots of the season, but second place is the 1st loser.

I know that a 223 is not in the same league as the 6BR but it is fun to give them a run for their money

I just ordered a 7 twist Brux to try, when it comes in I will get the 8 twist spun off and hopefully I will see a slight improvement......

 

[DBLNUT]

Well I am gonna try both, A 7 twist on the 223 to shoot either the 75,80 or 90's and I have a BAT "B" with a1-7.75 twist Brux 6BR being built

It will be interesting to see what difference a barrel change will make on the .223.

 

[Mozella]

If you want to try the 90s, just be sure you have plenty of freebore cut in the chamber/throat to seat them properly. Dave Kiff at PTG makes a reamer with 0.169" freebore specifically for the 90s, which is the one I used to have my chamber cut. ..... snip..........

You need not have the rifle rechambered. PTG makes a "Uni-Throater" throat reamer for a hundred and fifty bucks or so. It's dead simple to use and it's an easy way for a shooter to lengthen a too-short throat in order to shoot 90gr bullets.

No gunsmith required and you can do it without removing the barrel from the action.

 

[DBLNUT]

You need not have the rifle rechambered. PTG makes a "Uni-Throater" throat reamer for a hundred and fifty bucks or so. It's dead simple to use and it's an easy way for a shooter to lengthen a too-short throat in order to shoot 90gr bullets.

No gunsmith required and you can do it without removing the barrel from the action.

I have .078 of freebore now, this takes the pressure ring on the 80VLD bullet below the neck shoulder junction, it looks to me that the 80VLD should have about a .120-.130 freebore. I have a gunsmith near me that said he could lengthen the freebore, I might have him do it.

Anybody have any thoughts on what the optimum freebore is for the 80's?