You can just use the "green" spring supplied by Rock River and it run just fine.
No need to pay $25.00 plus shipping for this spring unless you just want to.
Hopefully, no one is buying/using the Tubb's flat spring just because they "want to". I like to think that most of us here make informed decisions based on the performance of their individual rifle and their needs (with respect to how they use their rifle).
Personally, I NEVER promote the wholesale acceptance of any product (or modification) based solely on what others are doing. Their needs might be different from mine.
On the other hand…it would be unwise of me to ignore/dismiss the findings of others….or take a “one size fits all” approach to the optimal tuning of the SOCOM.
Each person will need to decide if they want/need an extra power buffer spring (it doesn’t have to be Tubb’s C/S flat spring).
For my purposes…I decided it would be a good thing…provided I still got reliable cycling (usually more a function of proper gassing than anything else).
Although the SOCOM was designed to function with standard buffers and springs (and it does), that doesn’t mean it is the optimal “set up”.There is NO doubt in my mind that Marty did his homework before releasing his creation, but I bet he’d be the first to tell you…that a little “tweaking” can make an individual rifle or load….even better.
I had determined from the start that I wanted to use an extra power buffer spring….simply because the original spring was designed to strip a .223/5.56 cartridge
from the magazine and also provide an adequate amount of resistance to the BCG during recoil (the timing phase).
That has to be done (reliably) under a variety of conditions (I.E. Hot weather, Cold weather, weapon marginally clean and lubed). The original spring does that with relative ease, but you have to consider that a COMPLETE 5.56 cartridge weighs about 190 grains.
The lightest combination I can come up with in my SOCOM is when shooting the Lehigh 100 gr. bullet, total cartridge weight approximately 318 grains….or about 67% heavier.
Move up to a 300 grain bullet (most common weight) and we get a total cartridge weight of approximately 526 grains (depending upon powder charge, etc)…or approximately 276% heavier.
Bump it up to a 405 grain Remy (or other bullet in that range) and we get roughly 626 grains for total cartridge weight…resulting in an increase of approximately 328%.
I am going to load up some 510 grain bullets soon which yield a cartridge with a total weight of about 716 grains. So I will be trying to strip from the magazine….a cartridge approximately 376% percent heavier than the cartridge the standard buffer spring was designed for. AND it needs to do that under all the same conditions… (to be reliable).100 grain Lehigh:300 grain C/T BST:405 grain "Remy":
Hence… my decision to go with an extra power spring. Getting past the notion of an extra power spring (whether needed or not), another feature of Tubb’s C/S flat spring is its undeniable longevity over standard Music Wire springs. Standard springs…should give you something like 3-9 K cycles minimum before they fall below performance standards (measured length of a rested spring).
That might equate to a lifetime of shooting for some folks and a replacement spring is currently about $4.00 (add shipping). The Tubb’s spring will run you a full $20.00 more than that (shipping is the same).
So…what exactly do you get for that extra 20 bucks?
You get a Chrome silicon alloy spring that is heat-treated, stress relieved and shot peened to increase reliability and service life.
Testing has shown:
Less than 2% change in spring loading through 500,000 compression cycles
Duty rated for 1,000,000 cycles
Additionally, (in my rifle)….it got rid of that annoying “Sproing, Clunk” sound.
So for ME, the extra power, the increased life expectancy and the loss of that “toy gun sound” was worth it, but I leave it to each person to decide.
Just my unsolicited .000002 on it.