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Never owned a “boss” on one before any advice on settings would be appreciated in fact any info would help Setting this one up for a friend of mine And just want to get this little monster dialed in Going with a zeiss v4 3-12x56 and it’s a browning a bolt stalker Hoping this thing will shoot lights out when done

Depends on if your shooting factory ammo or reloads. I have a 1994 Browning Abolt II medallion 7mag with BOSS, the 1st year they came out. I never really played with the BOSS because it shot very well on the factory setting. The BOSS is nothing more than a barrel tuner and brake in one. You can also get the CR BOSS (conventual recoil) that is just the tuner part without the brake. I have both. Depending on what factory ammo you choose, they may or may not have a setting for it.

So, this is how it's done for factory.

- Go to website and look up sweet spots, if they have one, start there.
- If not, screw BOSS all the way in and zero. Turn out to setting 2, fire 3 rounds.
- turn out to setting 3, fire 3 rounds. If the rounds tighten up, go to setting 4. If group opened up, go back to setting 2.
- keep doing this until you see a trend going in the direction you desire.
- Groups will eventually get tight then start opening up again. Thats your sweet spot.
- Within each setting is a micro setting. If groups were tight 3 but opened up at 2 and 4. then start moving in .2 increments.
- You can eventually dial it in really tight. Just depends on what you're going to shoot. The CR BOSS and regular BOSS have same settings.

If you're going to load for it, then what I did was not worry about groups but finding a good velocity node at or near pressure. Don't worry about the groups because you'll be able to dial in that said group. I ended up with 3g higher than book max of H-1000 with 162 eld-m with no pressure signs seated .020" off the lands (this is a great thing about the Abolt, I'll explain in a sec) seated to 3.415" while Saami specs is 3.290". Once the velocity node was found, tune the same way starting with setting 2 and so forth. My LA Abolt II has a modified mag that will allow me to shoot up to 3.710" COAL. The issue that I have is my older 7mag only has a 9.5 twist, so some of the heavy more BC bullets won't stabilize. But it shoots those 162's like lasers. I'm low on H-1000, but the last set of rounds I shot with a 30-year-old rifle was .311 moa at 100 yards.

Here is a pic of my modified mag.

Mag with a factory length round



Mag was modified and material moved so that longer rounds could be used as well as seat bullet out further.



There is a metal rivet in the middle that holds the mag insert in place. Don't remove the rivet. I took the mag apart, and used one of my chainsaw files to make the groove so that the tips of the bullets wouldn't drag. The steel outer ring has an internal COAL of 3.715" and my action opening is slightly larger than that. But given the 162 eld-m's are seated out much further than Saami, I'm still within my modified length. So if your shooting 300 wm or similar to mine, the modified mag will really open things up for you and not constrain you.

Here is a short video that is 14 years old but explains how it works.

BOSS System

thank you gentlemen for the replies that should get me going