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CZ 457 MDT ACC build - LOT TEST

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https://sigforum.com/eve/forums/a/tpc/f/630601935/m/1410004025

April 23, 2026, 09:30 AM
pace40
CZ 457 MDT ACC build - LOT TEST
So as not to keep stepping on Todd's thread, I figured I'd start a new one to follow the build progress of my new benchrest rifle.

Step 1... (all I could afford this month Big Grin )

This message has been edited. Last edited by: pace40,


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Pace
April 24, 2026, 07:34 AM
pace40
OK...step 2...(yea, I know but my financial month starts on the 4th Wednesday)




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Pace
April 24, 2026, 07:57 AM
sigfreund
Keep us posted. Smile




6.0/94.0

“I can’t give you brains, but I can give you a diploma.”
— The Wizard of Oz
April 24, 2026, 07:59 AM
usncorpsman
I can’t wait to see how she shoots.
April 27, 2026, 06:20 PM
pace40
Step 3…

1. Polish bolt wear surfaces and channel
2. Install DPG Talon extractor
3. Install JARD trigger
4. Deburr barrel lugs and polish chamber face
5. Install Lilja barrel - headspace set @ 0.040
6. Install MDT 20 MOA scope rail
7. Install barreled action in MDT ACC chassis



Scope, ARCALOCK clamp, and Bipod should be here tomorrow and we’ll finish up.

Thought I would try a little lighter trigger, too.




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Pace
April 28, 2026, 12:57 PM
pace40
And we’re done…



Great timing since KSS just got new lots of Eley. I have a few different lots of Tenex and Match coming in as I’m getting a little low.



Looks like rain the rest of the week so I’ll lot test when I can. Should be an interesting exercise. My other Lilja likes Match at around 1060 fps. Would be very convenient if this one does too. Not pleased that it went up another dollar a box from last year though.


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Pace
April 28, 2026, 11:46 PM
captain127
Nice set up. The problem with lot testing these days is by the time you zero in on the lot that works best for you, it can’t be found anywhere! The massive increase in demand for match 22 ammo from the PRS/NRL crowd ( I am one of them) has made once plentiful ( even in times when other types of ammo were scarce or going for scalper price) match 22 hard to get consistently. I am a SK fan ( cheapskate won’t spring for lapua or tenex ) and often have to swap between long range, pistol match special and biathlon ( all in the same velocity range) just based on availability
April 29, 2026, 05:02 AM
pace40
^^^^^^^^^^^^^^^^^
Thanks! I hear you. I usually buy from KSS and pay great attention to amount on hand when ordering. Needs to be 200+ of any given lot so I can shoot it and have enough time to get back and grab a case when I find a good one. It usually works out. Think I only missed once in the last few years. My Lilja barrels are headspaced for Eley and won't cycle anything Lapua (including SK) reliably, so there's that. I stopped chasing Lapua anyway because it can go months before it's in stock again. At least Eley can keep up. Used to grab Team for practice but that's up over $17/box now so it looks like Club will be my go-to for that.

My Tikka, on the other hand, loves Lapua so I still buy for that but I'm probably going to drop the headspace in that for Eley too just because of ammo availability.


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Pace
April 29, 2026, 12:06 PM
got2hav1
I'd be interrested in hearing how that barrel shoots Eley. I've never had a Lilja barrel that liked Eley ammo. Looking forward to a range report.


JEREMIAH 33:3
April 29, 2026, 01:21 PM
pace40
^^^^^^^^^^^^
Have you tried dropping your headspace to set the lead in the rifling a little further? Eley spec is 0.040. My other Lilja shoots sub-0.20 groups pretty consistently @ 50 (with match ammo). I hope this one does too but have to wait for a break in the rain to find out.


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Pace
April 30, 2026, 10:21 AM
got2hav1
quote:
Originally posted by pace40:
^^^^^^^^^^^^
Have you tried dropping your headspace to set the lead in the rifling a little further? Eley spec is 0.040. My other Lilja shoots sub-0.20 groups pretty consistently @ 50 (with match ammo). I hope this one does too but have to wait for a break in the rain to find out.


I haven't messed with the headspace lately. It shoots Lapua really good but may have to try and adjust the head space as suggested.


JEREMIAH 33:3
April 30, 2026, 10:24 AM
got2hav1
On another note, just got my DPG rifle in. It's an older gun before he started threading the receivers. Check out that crown work. Hope it shoots good.






JEREMIAH 33:3
May 01, 2026, 10:06 AM
pace40
quote:
Originally posted by got2hav1:
On another note, just got my DPG rifle in. Hope it shoots good.


Nice DPG. I don't think you have to worry about it shooting. Pretty sure it wouldn't have left the shop if it didn't. That is, of course, a previous owner didn't Bubba it.

quote:
It shoots Lapua really good but may have to try and adjust the head space as suggested.


Depending on your preference, be careful if you headspace down to accuracy with Eley. Eley case rims are about .002 thinner than Lapua and Lapua extraction becomes an issue if you get headspace down to Eley spec @ .040. Talon extractors eliminate some of that, not all.


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Pace
May 01, 2026, 10:54 AM
got2hav1
quote:
Originally posted by pace40:
quote:
Originally posted by got2hav1:
On another note, just got my DPG rifle in. Hope it shoots good.


Nice DPG. I don't think you have to worry about it shooting. Pretty sure it wouldn't have left the shop if it didn't. That is, of course, a previous owner didn't Bubba it.

quote:
It shoots Lapua really good but may have to try and adjust the head space as suggested.


Depending on your preference, be careful if you headspace down to accuracy with Eley. Eley case rims are about .002 thinner than Lapua and Lapua extraction becomes an issue if you get headspace down to Eley spec @ .040. Talon extractors eliminate some of that, not all.


I'll probably leave that one as is. I am pretty sure it is set at .043" now and the barrel is glued in. I could use bolt shims I guess.


JEREMIAH 33:3
May 01, 2026, 06:27 PM
Todd Huffman
Very nice!!! Can't wait to see what it does.




Here's to the sunny slopes of long ago.
May 14, 2026, 11:15 AM
pace40
Finally got a chance to do this.

OK then…got some random lots from KSS and a couple of test bricks from Whidden. After a day of testing everything yesterday, I narrowed it down to the 5 best lots.
I’ll shoot 3 – 5 shot groups of each to pick the best. (More if the wind starts being a pest.) The leftovers will be for plinking and practice. Average group size, standard deviation, and extreme spread used to determine bulk order. And the winner …



Tenex lot # 04047 it is. Case on the way. (couldn’t be the cheaper stuff) Hopefully will last a few years, although I’m thinking of jumping into benchrest silhouette too, so maybe not.

Guess I'll have to keep the gun. She shoots pretty good. And the trigger is outstanding. Maybe I'll shoot that 25/25 this year. Big Grin


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Pace
May 15, 2026, 05:20 PM
got2hav1
Excellent work. That is a shooter for sure. Hard to beat CZ457/Lilja combo and you have a good one there! Congratulations.


JEREMIAH 33:3