HOWA 1500 .223 REM Chamber Dimensions Different Between Barrel Profiles

BlindSpider

Private
Minuteman
Oct 7, 2021
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0
Sydney, Australia
Relatively new shooter here, I've got a Howa 1500 in 223 short action, Varmint profile, 1 in 8'. I've spoken to another bloke who's wife has a M1500 with the sporter barrel she shoots out to 1000m. His reloads CBTO are 1.991' with a .005' jump to lands. Mine are 1.900 with a larger jump than his.

My issue is that I'm already starting to crunch powder with the 73gr 75gr projectiles I'm using and 23.5gr of AR2208. Am I right in thinking the difference in chambers is because Howa is expecting me to use a lighter projectile for *varminting*, compared to the sporter barrel.

From what I understand, I'll need to get a gunsmith to increase the freebore. Does anybody have any recommendations for a 223 chamber freebore with heavier projectiles, my plan was to seat CBTO to 2'. Is that sound unreasonable for a 75gr projectile? What should I be working with in terms of jump to lands?

Cheers
 

BlindSpider

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Minuteman
Oct 7, 2021
6
0
Sydney, Australia
What kind of velocities and accuracy are you getting with your current load?
No idea with velocities, have no way to measure. but after putting a proper stock on, I'm getting 5 shot groups sub MOA. The best 4 of those are easily .5", with some being cloverleaf/one hole.
 

BlindSpider

Private
Minuteman
Oct 7, 2021
6
0
Sydney, Australia
What kind of velocities and accuracy are you getting with your current load?
20220211_011400.jpg
 

jLorenzo

Sergeant
Full Member
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Feb 20, 2017
1,060
171
Good to know, is it marked on the barrel? Always a struggle to figure that out with other brands besides Tikka. At least its not easy to find immediate confirmation of the twist rate.
 

BlindSpider

Private
Minuteman
Oct 7, 2021
6
0
Sydney, Australia
Good to know, is it marked on the barrel? Always a struggle to figure that out with other brands besides Tikka. At least its not easy to find immediate confirmation of the twist rate.
I was actually expecting a 1:10 twist when I ordered it, wherever I found online said 1:10. I was pleasantly surprised when I picked it up.
 

MarshallDodge

At the Reloading Bench
Full Member
Minuteman
Jul 19, 2007
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1,544
Utah
Howa makes a 1:8 twist 223?
Yes, I have a mini Howa in 223 with a 1:8 twist heavy. It's a pretty good shooter, just under MOA.

I don't know how the bigger 1500 is but if you load anything beyond normal 223 pressures, it has a hard time extracting cases.