Re: Defiance Machine
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.Gordon</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.Gordon</div><div class="ubbcode-body">
Cons
<span style="font-weight: bold">1 </span>Possibly more expensive to manufacture
<span style="font-weight: bold">2 </span>Not quite sure if 3 lugs is stronger or weaker than 2
<span style="font-weight: bold">3 </span>Stiffer bolt lift because the bolt is unlocking, cocking and extracting in 60 degrees instead of 90.
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Mark-
I've done quite a bit of detailed hand calculations and finite element analysis on various lug configurations (up to, and including 6 locking lugs for a 30* throw).
With modern tooling #1 is really a non-issue.
#2 can be stronger or weaker, the configuration of the lugs, mating geometry in the receiver, materials, etc. have a large amount to do with the "strength" of an action. Taking the Sako TRG42 for example though, it is a very stiff bolt head. The Remington 700 has a stiff bolt head as well.
The difference that would drive me into a Sako design over a Remington design is the receiver lockup region and the stiffness of the design there.
There are a lot of things to consider between a 2, 3, or 4 (RPA Quadlock for example) but they can all be made sufficiently "strong" to never worry about stretching out the receiver under even what most consider harsh conditions.
The issue with #3 is recurring. You have a lot of room to do the work needed for cocking and extraction in a 90* bolt throw. The 60* requires that work to be done in 2/3 the distance and therefore all else being the same, the bolt lift will "feel" 50% heavier. On the RPA Quadlock the work is done in 50% of the distance and the bolt lift (again, everything else being equal) would feel to be twice as heavy.
There are ways to help mitigate these things as we've seen from the Badger Gen 2 action updates and the David Tubb replacement parts that many guys have run in them, but the fact remains that a short bolt throw causes a lot of "work arounds" to be employed.
This is probably the single biggest issue that many shooters and other engineers that I've discussed the topic with come back to. That is user interface and the tribology (generally perceived as the "feel") of the system.
ETA: The above comments are pretty far "off topic" from Mr. Roscoe's initial posts, so I'd like to just say in addition:
VERY NICE! I have a receiver on order from Skunkworks (also a Defiance procured action) and I have been dreaming about the day it arrives for some time now. I can't wait to get it in hand. </div></div>
Well thought out response. Looking forward to meeting up at SHOT, heck I might even let you buy me a beer! haha.
Mark </div></div>
Lookin' forward to it