6 Dasher freebore

[KWeigel]

I have read a lot of posts talking about different freebore lengths that people think work best. I would like to compile a list for reference what YOU guys found works well for yourself. This is my first Dasher so I am not a expert. Will be shooting either 105 hybrids or 107smk. I know some of you have a lot of experience with this and would love your insight.

Appreciate the help

 

[ridgeway]

I use a .136 FB. Anywhere between .125-.155 seems to be in the favored range for 103-108 gr bullets. One thing to consider with fat diameter bullets these days, might be wise to spec a .2438" freebore diameter on your reamer, or larger. I currently have a reamer with a .2435" freebore diameter and have another on order with a .2438" fb diameter. This is due to the fact that a certain manufacturer likes throw out bullets that are .2435"-.2438"-9 in bearing surface diameter. For example, a .2435" bullet does not like a .2435" hole!

 

[savagedasher]

I like .0130 plus for hybrids. But I shoot H 4350. Without that much free bore you cant get 36.5 grain in a dasher. Larry

 

[dkhunt14]

I use a .155 freebore. Ridgeway is right on. Most people use .135 to .155 to get the bullet out of the neck shoulder junction. It also helps to reduce pressure some. Matt

 

[Terry]

How far do you go before there in not enough neck to seat the bullet?

 

[Terry]

Do I have the math right?

.322 6BR neck length as shown on this site.
.222 Dasher neck length. (.322-.100 again per this site)

.222-.104 Old Dasher standard freebore = .118 to hold the bullet
.222-.150 freebore = .072 to hold the bullet.

 

[dmoran]

Terry,

Throat/Free-bore is not minus the neck, the throat/free-bore is after the neck........
Say you have a 104-FB with say a 105-VLD seated with the bearing at the junction (your .222 mark) and making contact with the rifling, you would have .222" holding/gripping the bullet. Extend the throat to say a .154-FB and you would have .050" less, or .172" holding the bullet to make the same contact with the rifling. And you will have changed the "Load Density" by around 2% in a 6Dasher case (hence, more capacity/less pressure).

Donovan

 

[johara1]

Alf. Neither do i…….. LOL… Maybe if you checked it on a optical comparator it maybe longer than you think……. jim

 

[KWeigel]

So if I am going to shoot either the 105 hyb or 107 smk with varget I should go with .155? In my experience both bullets like to be jumped. Hybrids 10 and the smk 30. Does this still jive?

 

[johara1]

I have found the 105H shot in better, but it will work with the .135 free bore and so will the 107's…….. jim

 

[dkhunt14]

in my experience the 107 Sierra liked it in. I also shot the 105 VLD and it liked it in. My experience with the Hybrid is limited but my gun liked it jumped a bit. Just never got them to shoot as good as the VLD.

 

[johara1]

Matt, It depends what lot you get, some do good and some you just wear out your barrel………. jim

 

[lloydx2]

What are you planning on doing with the gun.
Bench, varmints, f class, Prone sling. What distance
This all makes a difference.

 

[dkhunt14]

What are you planning on doing with the gun.
Bench, varmints, f class, Prone sling. What distance
This all makes a difference.

Makes no difference of use, only makes a difference on bullet used. If you freebore too short you will have bullet into neck shoulder junction and will pick up more pressure. With the 2 bullets he suggested I would be between 135 and 155. Both of these will work well with those bullets. It will just shoot better with these freebores.

 

[savagedasher]

I like my boat tail above where you can get the donut. Along with it gives more case capacity for H 4350 Larry

 

[dkhunt14]

Yes I shoot .155 freebore and used both of those bullets at 10 to 15 in.

 

[KWeigel]

Thanks dkhunt you answered it perfect for me. Just want to make sure that at .155 there is enough bullet left for jamming.