PDA

View Full Version : Need feedback on an Action that is mis-drilled, badly milled or twisted etc



tammons
04-13-2013, 08:35 PM
Have a flat back LA I bought off a member here. Good deal on the action but unknown history. Previously a magnum action and it was the dirtiest action I have ever bought. The Firing pin assembly was way out of spec so dont know what happened there except somebody monkeying with it that did not know what they were doing..

Just mounted a new EGW 20d base on it and I was setting it up to mount a scope with a digital level and the difference between the front and the back of the scope base is about 0.4 degrees twisted. IE if I set the back at 0 d the front is at 0.4 degrees.

Is this normal for savage flat backs ??

I am not sure if the action is twisted but it cycles about like any other savage.

I am also thinking I could have a bad scope base ??

Would a T+T fix this if its not the base ??

drybean
04-13-2013, 10:08 PM
Just use some Burris rings & be done with it

drybean





i

tammons
04-13-2013, 10:12 PM
Yes - True - but I am just curious is this is common for the action or bases or what.
0.4 degrees is pretty twisted, but I Guess I could try another base.

jonbearman
04-13-2013, 10:27 PM
Put a straight edge down it in 90 degree increments approximatlyht edge or see light under the edge.Its crude but it will give you some idea of how straight it could be.

BillPa
04-13-2013, 10:32 PM
Just mounted a new EGW 20d base on it and I was setting it up to mount a scope with a digital level and the difference between the front and the back of the scope base is about 0.4 degrees twisted. IE if I set the back at 0 d the front is at 0.4 degrees.

Is this normal for savage flat backs ??

I am not sure if the action is twisted but it cycles about like any other savage.

I am also thinking I could have a bad scope base ??



Chances are better than even the flat on the bridge isn't machined square, neither of my 10 FBs actions are.

What I would do, check the level on the base front to back with only the front screws lightly snugged. If it stays straight then I suggest bedding the action to the mount.

Bad base? Doubtful, but few seconds with a straight edge would confirm that.

Bill

kingzero
04-13-2013, 11:33 PM
Bed the base to the action.

tammons
04-14-2013, 12:47 AM
Funny I have one flat back that is perfectly square machined correctly etc. Base fits perfectly.
After taking out the rear base screws off this new action I can see where it needs to be bedded.

Thanks

quarterbore
04-14-2013, 01:22 AM
I have a flat back that was a complete pain. I ended up using the Burris signature rings, and raising the rear .020 and lowering the front .010. That gave me a total of .030 elevation in the rear and got me about centered in the middle of my scopes mechanical adjustments.

bootsmcguire
04-14-2013, 01:24 AM
Just had the same problem today with a new to me early 70s Flat Rear LA. Loosened the rear base screws on my 1pc base and sure enough there's a nice little gap. Between .010 and .015 near as I can tell without going out and getting my feeler gauges. Looks like I too have bedding to do.

squirrelsniper
04-14-2013, 02:03 AM
It is certainly more common with the flat-back rifles. I have read on this site that it has something to do with the final grinding/polishing of the action being done by hand, but I have no idea if that's actually true or just an internet theory, but it's the most reasonable explanation I've heard of why so many FBs have base fitment issues.

Aside from the old "tighten it down and it's good enough" method of scope mounting, the best solution is to simply bed the base. Usually you don't even have to bed the front portion, you can often just use the front screws to hold the base in the correct position while the bedding material is setting up on the rear.

Werewolf
04-14-2013, 11:11 AM
No, the flats being hand ground is true. It has been confirmed by folks like Mr. Furious and Sharpshooter in the past. Not too uncommon to get one thats just a "smidge" off somewhere.

tammons
04-14-2013, 11:45 AM
Interesting - with today's CNC machining etc, I would think they would all be close to perfect, but mine was way off horizontally (angle) and it was cut too deep. Probably an older action. However now it is bedded.

geargrinder
04-14-2013, 12:02 PM
Interesting - with today's CNC machining etc, I would think they would all be close to perfect, but mine was way off horizontally (angle) and it was cut too deep. Probably an older action. However now it is bedded.

You're correct. That's why they went to round rears, so they don't have to do any hand finishing.

jibben
04-14-2013, 12:21 PM
slim chance the barrel was removed improperly and it is slightly bent.

tammons
04-14-2013, 12:42 PM
I will most likely send it to SSS to have it T+T sometime in the future.