Centerfire rifle drop testing: Tikka/SWFA

[ElPollo]

I’ve used sandpaper around a rod, Dremel, knives, a hatchet, etc.

Hatchet?…. Fk yeah. Form cannot have nice things, for he is the destroyer of cats and firearms.

That said, I’ve actually used a knife as a scraper for opening Tikka barrel channels. It’s probably more controllable than a dremel. My dremeled Tikka stocks look sorta like they rode the NYC subway with a hungry rat.

 

[wyosam]

The whole way. Throw a dead cat through the gap.

Dead cat is about right. A channel that will fit a sendero light is just about right for most factory barrels.


Sent from my iPhone using Tapatalk

 

[Marbles]

What’s the best way to do that? Sorry for the series of questions and thanks for the reply.

A deep well socket and some 120 grit sandpaper makes quick work of it.

 

[HighUintas]

Anyone have a link to the drop procedure thread? I'm having trouble finding it searching.

Disregard. Found it

 

[Marbles]

Repeated it and passed. I switched to UM rings and remounted the scope, cleaned everything with acetone, and put blue loctite on the inside of the rings. Torqued ring cap screws to 35 in lbs, rings to rail at 50 in lbs. I also moved to 65 in lbs on the action screws. No other changes. It really is fun to "beat the shit out of" my Tikka as someone referred to it earlier in the thread.

Slightly different procedure. Dropped from bellybutton height (42 inches, but about 5 inches of snow, so about 36 inches) 3 times on the left, shot; three times on the right, shot; three times on the elevation turret, shot. As I'm playing around with powders and bullets, I shot a 30 round proof group to start. I also fired 4 shots checking zero as I tried moving it to PoA. I flubbed that, but that is why the string is 40 shots (and the group covered by my hand).

Snow had a half inch layer that was knife hard, but under this was very soft, first drop broke the crust, each time I started on fresh snow.




I was a fool and placed the target exactly over another target for this shot, you will have to look a little closer to see the shots. Figured as my zero was off, and I was several shots into by 30 round group before I realized, I would compare by drawing a reference with aim point marked.


Left drop.


Right drop


Top drop.

 

[HighUintas]

What do you think your failure point was previously?

 

[Marbles]

What do you think your failure point was previously?

In order of probability:

Possibly the wing nut behind the trigger was loose.
Possibly having the action screws torqued to only 45 in lbs.
Possibly I forgot to degrees the scope tube and it moved in the rings.

Applying a strict criteria, I stayed within the same 3.5ish inch area, so it did not shift. I'm inclined to think the 3 "flyers" reflected my shooting ability and ways I was effecting the gun, and the bulk of the rounds fell in a different part of that 3.5 inch circle because I was shooting differently a week later making the groups center shift without shifting the perimeter.

 

[D L]

Marbles, thanks for posting this thread. I think it’s great to be able to watch you walk through the troubleshooting process and eliminate possible causes of your zero shift. This is immensely helpful as I will be walking through this same process on two new Tikka rifles.