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View Full Version : The low-down on M4 springs...



Unobtanium
08-21-2008, 02:14 PM
Okay...I called Benelli today. After being thrown around on hold and waiting 15 minutes (I felt bad for the operator, she sounded like this was a college job for her and I could all but feel her cringe when I said "Hi, you put me on hold and I waited 10 minutes and the system directed me back to you". Completely understandable, but I work with people all the time and always have, so I empathized...ANYWAYS>..)

Benelli finally got to me on the phone. I was informed that there is ONE! spring for the M4. It's part number is:70053

But wait...

I have seen part number 70052 bandied about on this forum as well! Is benelli misleading me?

Well, I asked the nice lady to punch in 70052. Turns out this is the part number for the mag tube itself.

SOCOMguy is correct. There is only one factory spring for the Benelli M4. It is meant to go with the factory 5 OR 7-shot tube.



I am going to go and test things out with the Benelli follower and stock spring, as it is what SHOULD be in there according to Benelli. (Also, I find it quite telling that it has MORE tension on the last round than does the SRM M4+2 spring they sell with their kit. All evidence points to the rep I spoke to at Benelli being correct).

Also, if you look at the "extended spring" on the e-guns site that is recommended with their extended tube ( TUBE: http://www.e-gunparts.com/DisplayAd.asp?chrProductSKU=981490&chrSuperSKU=&MC=

SPRING:

http://www.e-gunparts.com/product.asp?chrProductSKU=981390&MC= ), its Benelli part number: 60479 (acertained by a call to E-guns). According to Benelli (and E-guns when you click on this part number), this item fits: M1/M3 Super 90 and is a factory type spring. NOT extended capacity (which Benelli only offers if you get a +4 or larger extension, and not at all for the M4 model).

I have thus spoken with 2 Benelli Reps and both of them have told me 70053 is the ONLY spring spec'ed by Benelli for the M4. Reguardless of the mag tube. The fact that I have not found any other spring online made by Benelli for the M4 confirms this.

There you have it, 1 hour of my day spend fiddling with mag-springs and data to put this to bed.

Duggan
08-21-2008, 03:49 PM
SOCOMguy is correct. There is only one factory spring for the Benelli M4. It is meant to go with the factory 5 OR 7-shot tube

I've being saying that for ages. I've never used anything but the factory spring that came with my m4.

Good investigating though, it's nice to have some confirmed data concerning this problem that has popped up since people/vendors started going aftermarket spring crazy.

No F-Bdy Bs
08-23-2008, 06:29 AM
Thats my understanding also. Regardless of the tube length, there is 1 spring.

I got an extended spring with my DMV tube. Forgot to install it, and my M4 works fine.

I cant see how a longer/higher tension spring would hurt anything. The only thing its gonna do is get the shell into the receiver faster.

I dont see it hurting either way.

Westro
08-24-2008, 11:48 AM
I'm in the same boat here, having trouble finding an extra strength spring for my father's M2. I know with a 2 shot extension on my M1 the stock spring is fine. But my father's M2 with a stock spring he is having cycling feed issues.

Anyone know of a spring to correct this? I see that Wolff spring doesn't offer anything for extended mags.

Unobtanium
08-24-2008, 04:35 PM
Buy the M1 Super 90 spring for "military/LE" from Brownells. That is what I am about to do. My M4 spring works well except on 3" OO buckshot and the like, where the kick and mass of the shell in the mag-tube keep it from kicking the shell out fast/hard enough to get it on top of the carrier in time to lift it before the bolt slams home.

Also, click on the "ALT" button when you find the spring, it will show you a 40" WOLF spring.

johnnywitt
08-28-2008, 12:12 AM
OK, I measured the factory spring and it was like 27" and the Egunparts "Benelli" spring was 39" and I put it in- IT WAS A BEEOTCH!

My M4 can now only hold 6 2.75" rounds. The stock spring works fine and I'm sending the Long Spring back to Numrich for a refund. I even left the spring compressed for 3 days with 6 shells in the mag and I can't get the 7th shell in the gun, no way, no how.

Unobtanium
08-28-2008, 12:45 AM
OK, I measured the factory spring and it was like 27" and the Egunparts "Benelli" spring was 39" and I put it in- IT WAS A BEEOTCH!

My M4 can now only hold 6 2.75" rounds. The stock spring works fine and I'm sending the Long Spring back to Numrich for a refund. I even left the spring compressed for 3 days with 6 shells in the mag and I can't get the 7th shell in the gun, no way, no how.


Hrmmm, I got 2 of those springs, one was 39" and one was 35" on the nose. The 39" quickly went to 35" after being installed and removed.

Try using another brand of shell. Some are longer than others.

My stock M4 spring fit just fine, and it ran fine, until I run 3" buckshot, then the recoil prevents the spring from properly ejecting a shell on top of the carrier fully.

metroplex
09-29-2012, 09:54 AM
The Nordic spring is 45" OAL. If the Benelli OEM "Long" spring (60479) is 39" OAL, then that would make it 22.5" longer than the +5 extension tube on a M2. Nordic recommends a length of 12"-16" beyond the extension, so I cut my Nordic to 14" beyond the +5 extension which is about 30.5" OAL. It sounds like going with a cut Nordic spring is still the best route for those going with an extension tube.

heckler&kochp2000
09-29-2012, 09:58 AM
I use the 70053 Benelli Original factory spring in my 70052 Benelli Original factory magazine . Never had a problem .