Benelli M4 Tip: Dialing In the Recoil Tube for a Straight 70085 Collapsible Stock

In this post I explain my simple, repeatable process for aligning a Benelli M4 recoil tube so a 70085 collapsible (skeletonized) stock sits straight at true 12 o’clock. I cover why minor cant happens, how to confirm it’s a recoil-tube indexing issue (not the stock), the mock-fit/no-Loctite step, reference depth and notch cues, and the silver Sharpie trick that lets me hit the exact alignment again when I set threadlocker. If you’re building or tuning a Benelli M4/M1014, this is a quick win for cleaner ergonomics and sight alignment.

0:00 Intro & what I’m fixing (crooked collapsible stock)
0:12 Goal: true 12 o’clock alignment without wobble
0:25 Sub/notify & how to reach me for help
0:41 Why some M4 stocks sit slightly canted from the factory
1:00 What “crooked” looks like (11:56 / 12:04 examples)
1:23 It’s the recoil tube position—not the stock body
1:42 Reference measurements & visual alignment cues
2:31 How I mock-fit: no Loctite, test alignment first
3:02 Marking with a silver Sharpie to repeat perfect alignment
3:34 When I would (and wouldn’t) redo a factory tube
4:12 Final set with threadlocker & straightness checks

Today I’m tackling a common Benelli M4 question: how to dial in the recoil tube so a 70085 collapsible (skeletonized) stock sits perfectly straight. Many M4s show a slight cant from the factory. That small lean—think 11:56 to the left or 12:04 to the right—usually comes from where the recoil tube is indexed, not from the stock itself.

Here’s how I approach it. First, I mock-fit without Loctite. I thread the recoil tube into the receiver, install the stock, and check alignment by eye and with simple reference points. I look at the tube depth past the receiver and the index cuts/notches on the tube. On many OEM setups I see roughly about 1/2 inch of threaded section exposed at the nut before the main cut starts further forward; your exact measurement can vary based on how the receiver and tube threads mate. I use those cues to get close, then I mark alignment with a silver Sharpie—small dots or lines on the tube and receiver that let me return to the exact “true” position.

If I’m re-tubing a gun, I’ll assemble and disassemble two or three times to confirm I hit the same straight position every pass. Only when I’m confident the stock sits at true 12 o’clock do I remove parts, apply threadlocker to the recoil tube threads, and reassemble—using my Sharpie marks to land in the same spot. I do not Loctite mag tubes, but I do Loctite recoil tubes so the stock won’t walk the tube during adjustments.

Should you redo a factory tube if the cant is barely visible? Personally, I don’t unless I’m already swapping tubes; the deviation is often minimal and purely cosmetic. But if you’re installing a new tube or the lean really bothers you, this mock-fit → mark → verify → Loctite workflow gives you the best chance at a perfectly straight Benelli M4/M1014 collapsible stock.

If you have questions about parts or setup, text or call me at the number on my website—I’m around year-round to help you build the M4 you want.