Thread: 6x45 Rem barrel

Originally Posted by 57jl

I have the same marked Zastava Serbia CAL 223 REM 1KM85 it has a single set trigger and is a lefthand action

@57jl i stupidly so my zastava lh mini if your interesting in selling drop us a pm 😎

Its been a busy first week back at work but found some time to machine and pre-chamber the Sako Vixen barrel to fit up this weekend. Will then focus on the Zastava builds. Still not sure if Ill put a 6x45 barrel on one of the Zastavas as I might just put a new .223 barrel on it and move it on.



On a side note a new magazine arrived for my CZ 527.
Those of you that have messed with wildcat cartridges will know that some can have their vices in factory rifles.
The 6x45 was no exception.. I have been getting quite a few failures to feed due to the fatter 6mm necks binding in the sidewall stampings in the mag designed for the .223 Remington.



It is an easy fix by milling out the slots in the pressed section on both sides which I have done in the past for .300 BLK builds but CZ have actually just released a CZ
527 in .300Blk and listed spare mags for it.
These mags are made without any side wall stamping so feed the 6x45 rounds perfectly in my rifle. WINNING!

@Wingman, be keen to see some posts on the Sako Vixen fit up and your findings

Originally Posted by Mathias

Shit that HnF thread is nearly 3 years old. I've run a heap through mine in that time. Currently have a second 6x45 in the works, this time its gonna be 1:8 @ about 20" and lighter, esp after handling @southernman little Cooper

Originally Posted by Mathias

@Wingman, be keen to see some posts on the Sako Vixen fit up and your findings

The Vixen should be a fairly straight forward rebarrel.
It has a internal .223 mag with a max COAL of 58.5mm, so the same as my CZ 527 mags.
It has a custom carbon fiber Stug stock fitted so as long as that has been bedded properly and the bottom metal is fitted correctly in the position it was in the walnut stock it should feed fine.
The barrel inlet channel may need a little tickle up but other than that it should be great.

Ok so the Zastava pushed inline.
I have made a start on the M85 instead of the Sako as my weekend penciled in for workshop and load development time was sidetracked by a sick wife and kids. They are on the up now so I spent the evening prepping the Zastava and rescheduled the Sako fit up.



The Zastava M85 aka Remington 799 aka Interarms MarkX etc it's not actually a true mini mauser, if my info is correct its is based on the Sako L46 action.
It’s a small-action Mauser, true to its namesake’s double-lug form, with a claw extractor and standard left-side bolt release but it is not a controlled feed. It has a sako type extractor.. infact wit a little filing the Sako extractor can be used as a replacement for the commonly damaged Zastava units.
It’s very lightweight, at just over five pounds empty, *Overal the exterior metal on the M85 is well-finished. There’s a modern thumb safety, a gracefully-shaped trigger guard, and hinged floor plate. The magazine holds 6 rounds but feeds better with 5.

The first thing I notice with the M85 is the short length of the .223 internal box magazine. This will restrict 6x45 loads to about 46.5mm compared to the CZ 527 and Sako Vixons 49mm. Im sure they will still shoot great as shown in previous posting of early projectiles with a big jump to lands.
This is a 75gr Sierra hollow point seated for my CZ mag



This one is getting a 1-10" twist barrel so will handle the heavier projectiles as well.

With the pitted out .223 barrel removed and action stripped I have also noted some ugly machining.



While the bolt is quite slick in this one the actions face, and locking lug surfaces were very ugly.
With a bit of dye on the lug surfaces and a few cycles of the bolt it showed very little lug contact on one side (about 30%) and the other side was very marred from the factory machining process.
I tried to get good pics but it really doesnt show up well.






These surfaces will all get squared up with the bolt and lapped to full contact on both locking lugs.
Unfortunately I forgot to take pics of the dyed surfaces but the marred up shiney spots gives you some idea.

😎

I got the action all trued up, barrel threaded both ends and chambered.
I polished a few rough edges on the bolt/bolt channel and burnished in some molly powder which made it very slick.





The new barrel was a slightly bigger profile so the stock needed a little more inleting and will get a touch up with some stain and oil.



Finally reassembled it and threw a scope on to test on some paper tomorrow. The rings are too high but will do for testing purposes.



I put a few of my 75gr HP loads for my CZ through it over the chrono and they were a bit hot for the faster twist so will drop a grain and load some to mag length for the tests.

geez that m85 looks mint 👍😎👍

Yep shes pretty tidy now.. Ill work a load for it shortly and throw some lead on paper.
I managed to save 21.5" of the donor 6mm barrel and it shoots 55" faster than my 22" with the same loads! Will back it off to more brass friendly loads and go from there though. 2950fps seems to be a happy spot for the 75gr Sierra HPs and H4895 but will give the H335 a go when @Tommy visits.

@Wingman keep up the good work and thread
one day stars will align and ill join the 6x45 crew 😎👍
i read on a oz forum many moons a ago that 6mm varmint projectiles work like hunting ones less explosive at 6x45 speeds be interesting to see if true or just internet scuttle butt

Cheers mate.
There is some truth to that theory. SOME varmint and target bullets act like hunting bullets at lower velocities but that depends a lot on range and the bullet.
The 6x47 for example at 3000fps is not actually that slow. I would stay away from the lighter jacketed bullets such as 70gr blitzking, 70gr and 80gr Sierra varminters for anything heavier than goats and stay away from that shoulder bone. The 75gr and 85gr Sierra varminter had have heavier jackets designed for the bigger case .243s at 3800 to 4000fps so these are the ones you want in the 6x45 for deer.

Typo in that last post.. 6x45 @ 3000fps not 6x47 but both are true

Something else to consider is the lower BC of many of the flat base type varmint bullets. They wash of speed much faster than the longer more slippery hunting bullets. I would consider this 6x45 a 250 to 300yard max hunting rifle.

Originally Posted by Wingman

Something else to consider is the lower BC of many of the flat base type varmint bullets. They wash of speed much faster than the longer more slippery hunting bullets. I would consider this 6x45 a 250 to 300yard max hunting rifle.

Good words there @Wingman, it's a 300yrd round and no more. I've treated it exactly the same and haven't got myself into trouble sticking to the self imposed rule when used on goats.

How are you getting on with dies? I did post earlier that you can make a FL sizer from 223 bushing type dies easy enough. Redding do not list a 6x45 in their S Type, so I made one myself and it works a treat with the .263 bushing for my brass.

Originally Posted by Mathias

Good words there @Wingman, it's a 300yrd round and no more. I've treated it exactly the same and haven't got myself into trouble sticking to the self imposed rule when used on goats.

How are you getting on with dies? I did post earlier that you can make a FL sizer from 223 bushing type dies easy enough. Redding do not list a 6x45 in their S Type, so I made one myself and it works a treat with the .263 bushing for my brass.

I ordered a set of Reddings from my buddy in the states but had been using Southerman's set while he is back in Canada.

I had thought to make some from a .223 rem set of bushing dies and just run the reamer through the seating die but by the time you have done all that and bought a 6mm seating stem, neck bushes and expander balls etc it gets pricey. Robert at workshop innovation can order a set for I think it was $145 in his monthly Redding order.