Thread: Howa Mini Action Mainspring

Wondering if anyone else has installed a softer main spring on one of these. I find the bolt lift on mine quite stiff, enough to be annoying compared to my other bolt actions

I had the same issue with my 223 HB Mini and considered a softer/modified main spring. But in the end, I smeared bore-paste/lapping compound over the bolt spring and ran it through the bolt-body a number of times to ground down the high points to achieve less resistance and smoother/light bolt lift when de-cocked. This also allowed the cleaning out of factory gunk. I also smoothed the bolt cocking-ramp with some 1200 wet & dry and the bolt-head itself. You will notice there are some high points on the ramp itself which can be sanded/polished smooth. All in this work took me less than 30 mins including cleaning and re-oiling parts, now I don't need to take the gun off my shoulder to cycle the bolt.

Originally Posted by Trigger

I had the same issue with my 223 HB Mini and considered a softer/modified main spring. But in the end, I smeared bore-paste/lapping compound over the bolt spring and ran it through the bolt-body a number of times to ground down the high points to achieve less resistance and smoother/light bolt lift when de-cocked. This also allowed the cleaning out of factory gunk. I also smoothed the bolt cocking-ramp with some 1200 wet & dry and the bolt-head itself. You will notice there are some high points on the ramp itself which can be sanded/polished smooth. All in this work took me less than 30 mins including cleaning and re-oiling parts, now I don't need to take the gun off my shoulder to cycle the bolt.

Just gave this a go but no joy. Polished the cocking cam mirror smooth and found that the striker assembly is galling it as if cams. Bummer. I still think the spring is way to strong tbh.

Any luck sorting this? I'm pretty happy with how smooth the action is doing similar to the above but the initial bolt lift after firing is heavier than what I'd consider reasonable

Try the bolt lift on a ruger american, you will never complain about the howa again.
I found the bolt handle a little small and fitted a rubber tikka bolt ball that fixed the problem and the small amount of extra length make it a really easy 1 finger open job now.

When I first got mine brand new, I cycled the rifle in my shoulder at least 500 times to wear in the bolt and 300 times with the trigger decocked. This was before the mods I told Beavis. I also previously used the Tikka rubber knob for approximately 10 months, which was an excellent and inexpensive mod but I outgrew it and went onto the clamp-on type which suited me better.

Originally Posted by Bill999

Any luck sorting this? I'm pretty happy with how smooth the action is doing similar to the above but the initial bolt lift after firing is heavier than what I'd consider reasonable

@Bill999 I had another go. Polished the cocking cam alot more aggressively, mirror finish. Then I applied a heap of moly grease on every moving part of the gun. Significantly improved the feel. I still think a slightly lower power mainspring would make these a lot nicer to cock. I was able to play with a couple unfired minis last night and that feel like they have sand in the action compared to mine.

Yeah I had a play with a friends new heavy barrel and like you said it felt loads rougher
The extra weight even tho it's bugger all made that initial bolt lift easier
Bieng bloody light seems to make it more difficult and it pulls me off target in between shots
I still think it's a heavy mainspring issue as my tikka has the extra heavy mainspring in it and it's still a lighter bolt lift and sounds like it's less destructive when dry firing as unscientific as that is.

I'm wondering if it's to make sure all the hard primer military stuff goes off

Originally Posted by Bill999

Yeah I had a play with a friends new heavy barrel and like you said it felt loads rougher
The extra weight even tho it's bugger all made that initial bolt lift easier
Bieng bloody light seems to make it more difficult and it pulls me off target in between shots
I still think it's a heavy mainspring issue as my tikka has the extra heavy mainspring in it and it's still a lighter bolt lift and sounds like it's less destructive when dry firing as unscientific as that is.

I'm wondering if it's to make sure all the hard primer military stuff goes off

I'm not really brave enough to trim a coil off until I know of replacement springs. My friends Mossberg MVP 223 is effortless to cock, the action on that you can run super fast, never had any issues firing military ball.

The cocking cam, depending on your rifle can be crudely cut. Mine came with dremel like marks, almost reminded me of my Mosin 91/30 bolt. I smoothed and evened the Howa Mini's cock notch by approximately 0.005" to achieve a shorter bolt lift (could have smoothed even more) which translates to an overall lighter lift. However do note the Howa is a 2 lug, 90 degree bolt lift and lowering the cock notch by too much, there will be a point of no return.

The shoulder on my 223mini Hb bolt lugs are galling up a beaut, plan to moly the crap out of it and just monitor it. @Wingman reckoned it had either missed or had a shit hardening job. It's a real shame as it's so nice and accurate for the coin