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Thoughts on the MCARBO Trigger Spring Kit?

Would something like this be a good upgrade for home defense? Or would I be better off leaving the OEM spring in there? Basically, this one takes the pull from 5lbs 2oz (OEM) to 3lbs 5oz. Would light primer strike be an issue at all? Would it negatively effect rapid fire?

(It would be in conjunction with the full Or3gun kit and the SBE Precision Piston)


https://www.mcarbo.com/mossberg-930-/-935-trigger-spring-kit.aspx - $12.95
 
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For $13, its not a huge investment to try. I generally do not use RP trigger return springs in anything, as it is too easy for me to outrun the gun.
 
As was said, wouldn't hurt to try, but I'd run it a bunch to make sure it didn't make the hammer too light and suffer from light strikes or cause battering from the bolt having an easier time running over the hammer would be my biggest concerns.
 
For $13, its not a huge investment to try. I generally do not use RP trigger return springs in anything, as it is too easy for me to outrun the gun.
I suppose in a serious situation my goal wouldn't be to shoot as quickly as possible, relatively speaking (it'd still be fast but it wouldn't be wild and uncontrollably fast). But I'd be interested to see if this made the whole process smoother with zero downsides. But you're right, $13 isn't a big deal to give it a try at least.
 
As was said, wouldn't hurt to try, but I'd run it a bunch to make sure it didn't make the hammer too light and suffer from light strikes or cause battering from the bolt having an easier time running over the hammer would be my biggest concerns.
I understand the light strikes but what's the battering from the bolt having an easier time running over the hammer? This is all new to me.
 
The bolt pushes back over the hammer as it cycles and re-cocks the hammer.

If you lighten the hammer spring, the bolt is going to have an easier time pushing back over the hammer, and it may cram into the back of the receiver harder. Thus, battering the rear of the bolt into the receiver.

I'm not saying that it will batter the parts, but you would need to keep a close watch on it just to make sure no damage is being done is all.

It may not. Or, it may. Especially with hotter loads. It's just something you should be mindful of and watch for if you reduce your hammer spring weight.
 
Thus, battering the rear of the bolt into the receiver.
Firstly, I've never had a 930 apart in front of me so I could be talking out my arse. ;) I think there is a buffer to help prevent battering and also a "return spring assembly" that many semi-auto shotties don't have... How these will factor in regarding decreasing wear and tear, I don't know... (cutaway courtesy of Mossberg)

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Well, if there is a buffer in there, just make sure it's not getting chewed up.
 
I’ve installed them in all my 500 series pumps and both my 930’s. I tried one first and was satisfied with the results vs the price so I upgraded them all. The trigger is noticeably better and no adverse issues at all.
 
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^That's good that you've tried it with no ill effects.
 
The trigger spring is separate from, and independent of, the hammer and action springs. A lighter spring will make the trigger pull lighter and easier.

The hammer spring (OEM) is considered light by many, and there were a fair number of reports of light strikes, leading innovative users to replace the 930 hammer spring with a +P Ruger 10/22 hammer spring (same diameter but heavier weight). Hammer spring weight is the last action spring, in most any firearm, that you reduce in weight for "shootability".

The mainspring (in the receiver tail) most directly effects the bolt and cycling. Unless you dramatically reduce the mainspring weight, you have no danger of bolt/receiver battering. OR3Gun's adjustable MSR allows a reasonable amount of adjustment for a wider variety of loads with no risk of damage to your weapon.

If you were to increase the hammer spring weight to adjust for some uber-hot Round of Anihalation, in the 3.5" range in a rechambered 930, you would peen or fracture the hammer before having significant effect on the bolt.
 
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