Howa Mini Action reloaders COAL / CBTO

[Briano23]

I like to start this thread about COAL / CBTO. For the sake of conversation if the Howa Mini Actin measures 2.315" to the lands where is a good staring point for bullet jump.
When I reload my 308 I take and empty case and seat a bullet long and with the firing pin and ejector remove I keep seating the bullet to till I get a light contact closure on my bolt and call that my max OAL to the lands measure that with my comparator and start my reloads .015 to .020" back from there.
I know different bullets will require different jump lengths or seating depths and not knowing the function of the 6.5 Grendel bullet jump could someone explain how to determine how much bullet jump is required for the 6.5 grendel.
Thanks
Briano

[kmon]

I start out at max length to function through the mag reliably and test for bolt closure from there, if not into the lands that is where I start load workup, if that puts me into the lands shorten until just touching the lands and start from there or depending on bullet profile set jump may or may not work best.

Many rifles I have loaded for, max mag length does not reach the lands and I do not want to turn a repeater into a single shot just to load a particular bullet or for more case volume.

[Briano23]

Thanks, Right now I will Install a Hinged bottom metal instead of the magazine so hopefully I can get a little more OAL on my loads.

[jbmarshtx]

I'm shooting the barnes 100ttsx in my howa HB for hunting. I'd been using some factory Alexander Arms 120tsx ammo that I got on sale. For my Remington bolt actions I do the same as you for distance to the lands. I was not able to remove the ejector from the howa, and my online search revealed that without a super punch to remove the pin...many others had the same issue. I used the sinclair tool to find the approximate distance to lands. I had not done this before, so I don't know how accurate it was.

Anyway, I got a COAL of 2.308, and CBTO of 1.7645 for the Barnes at the lands or close to them. Usual disclaimer that this is what I found for my rifle. I settled on 29.0 gr VV133 and ~80 thou jump for a CBTO about 1.685 and COAL of about 2.226...if I measured everything correctly. This gave me a sub moa 5-shot group at 100 meters. I don't think that I have 100 rounds through the barrel yet.

If you can't get the ejector out and/or don't have a hornady/sinclair tool, I think that kmon's method would at least as good.

Edit to add...it really depends on the bullet and what you are using the rifle for as the longest COAL may not necessary be the best.

[Briano23]

I have the Sinclair ejector removal tool that can hold the ejector compressed to punch the ejector pin. Hopefully it will work.

[Briano23]

Just took my bolt apart removed the firing and the ejector with the Sinclair ejector removal tool ejector pin taped right out.

[wannabustbunnies]

I remove the firing pin assembly, put a fired case onto the bolt face and use a quick clamp from the back of the bolt to the case mouth to hold it in place. That keeps pressure on the ejector spring and it comes out easily if you punch from the bottom of the bolt to the top. Same thing to put it back together but pin in from the top of the bolt. Works no problems at all on my 4 Howas as long as you knock the pin that direction.

[Briano23]

Correct explanation.
Thanks

[jbmarshtx]

I might try that if I need to find the lands on the howa. I might have been attempting the punch from the wrong direction based on your post.

[wannabustbunnies]

It shouldn't take much force at all if you punch from the bottom. I might do it again in the next couple of days just to see how much jump my 90gr TNT'S have. They are loaded at 2.195" so I am guessing it is going to be alot

[jmkhenka]

Why bother with removing ejector etc?
Just take a cleaning rod or any wooden rod, longer then the barrel + action..

run rod through barrel until you come out of the action, align it with the center of the bolt and close it. Mark the rod on the end of the barrel (use a knife, or pen). Now remove bolt and insert the bullet. Take another rod from bolt side. With this and the long barrel-rod you now have the bullet fixed inbetween, now you should also be able to move the bullet back and forth and you will feel it hitting the lands. Now find a possition where the bullet sticks, but just barrely.. now mark the rod.

the two marks are max COAL.

You can also do the split necked case, just insert a bullet and close bolt.. then measure the COAL. Repeat a couple times. Later verify with a properly seated bullet in a calibrated case, if its to long it will show marks of the lands.

But chasing lands is pointless. If a bullet does not group in any load range with documented COAL, it wont do it just because its close or into the lands. Only reason why i bother with this is when i have a new bullet that im not sure about COAL on.
Magazine is often the max anyway, 58mm in my howa mini. bullets that work for me work in almost all coals from 56 to 58.

[wannabustbunnies]

I only use it as a reference point and for the sake of knowing. I'm not going to be able to get near the lands with the 90gr and mag length but I also have some 123's to try as well, once again just information to know.
I set up the sizing die with the bolt stripped as in the Wheeler Accuracy video as well.

[Briano23]

This is the method I use.

https://www.youtube.com/watch?v=TWmIwPwLyyg

So with my original post has anyone used this type method on the Howa to find there lands, if so what kind of numbers are you seeing?
And how far are you off the lands for your seated bullet?
Any bullet type data would be great.

[wannabustbunnies]

I measured with my mini action today with 90gr Speer TNT, 123gr SST and 123 ELD-M and got the following numbers to the lands.
90 TNT: 2.223"
123 SST: 2.295"
123 ELD-M: 2.290"
I might have to double check the TNT'S

[Briano23]

Thanks very good data.