Browning BPS 20 ga. hunter accuracy horrible

Sig_Dude · August 30, 2010, 08:58 AM

Yesterday I took my BPS 20 ga. to the range to sight it in. This shotgun has a rifled "deer" barrel. I had a load of Remington Buckhammer sabot slugs.

As I always do when I sight a gun in, I fired one shot so see where I was. I was 15 inches low (seemed really low). Adjusted the sight up 10 inches, then fired a group of 3. The "group" was 6".

Fired anotuer group: 7"

3 more groups, all between 5 and 7 inches.

Didn't bother to go any further.

I was really hoping to see 2" groups with this particular setup.

Am I expecting way too much or is something wrong with my rig?

Thanks!

Dave McC · August 30, 2010, 09:27 AM

When pump guns shoot like that, something is usually loose. Make sure the barrel is tight to the action, make sure the scope and mounts are tightened and Loctited,etc.

And after you check, have someone else try a group to eliminate the human factor. Benchtesting really brings out the recoil mule.

hogdogs · August 30, 2010, 09:43 AM

Are you using some super high quality rings?

When the scope stop came off one of my air rifles on a diller hunt, I had to retorque the dove tail joint connection as the scope was slipping rearward each shot.

By the time I was home, I had severely bent the screw and ruined the scope rings as well as the opposite side "tab" that bites the other side of dovetail.

Brent

Sig_Dude · August 30, 2010, 09:56 AM

I am using Leuopold low-mount rings...they are built like a tank. The way I install my scopes is as follows:

I have a piece of 1.000" ground rod with a handle on it.

I mount the lower ring halves to the pic rail, red Loctite them and torque them up to spec with my Snap-On in-lb wrench. I then lay in the 1" ground stock and install the upper rings over that...so the ground rod is where the scope would be. I apply some Wheeler Engineering lapping compound to the rod and start working it. When working it becomes easy, I tighten down the upper halves a little more. Do this for a while, then take apart to inspect. Make SURE you mark the upper halves and even the screws so they can go back where they came from. You will note that some off the pain/coating is gone from the inside of the rings. This shows your effective contact area. I then re-install the rod and work the lapping compound some more...repeating the aforementioned steps until I have zero paint left i.e. 100% contact. I then stiwth to a higher grit compound and really polish those ring ID's in. When I'm done, the rings look beautiful.

I then install the scope with red Loctite and spec-torque the upper screws. The scope will NOT move throughout a lifetime...it simply won't.

By the way, do not worry about using red Loctite...if you ever have to remove a "red" screw, simply touch the tip of a soldering iron to the screw head for a few moments and then they will back right out.

Anyway, I am certain the scope is mounted right, maybe the barrel is in fact lose. Thanks for the heads-up!

hogdogs · August 30, 2010, 10:59 AM

YEP!!! Sounds like it ain't a loose scope... rule out that possibility!

Brent

Doyle · August 30, 2010, 12:09 PM

Try a different brand of slugs. I've said MANY times on this forum - slug guns are notorious for perferring one particular brand of slugs and hating another.

highvel · August 30, 2010, 07:46 PM

Yes, definitely try different slugs, my Rem 870 shoots Winchester Supremes very good but will not shoot the lighter jacketed slugs worth a hoot!

August 30, 2010, 08:58 AM	#1
Sig_Dude Senior Member Join Date: June 25, 2010 Location: Southeast PA Posts: 115	Browning BPS 20 ga. hunter accuracy horrible Yesterday I took my BPS 20 ga. to the range to sight it in. This shotgun has a rifled "deer" barrel. I had a load of Remington Buckhammer sabot slugs. As I always do when I sight a gun in, I fired one shot so see where I was. I was 15 inches low (seemed really low). Adjusted the sight up 10 inches, then fired a group of 3. The "group" was 6". Fired anotuer group: 7" 3 more groups, all between 5 and 7 inches. Didn't bother to go any further. I was really hoping to see 2" groups with this particular setup. Am I expecting way too much or is something wrong with my rig? Thanks!

August 30, 2010, 07:46 PM	#7
highvel Senior Member Join Date: January 21, 2010 Location: Powhatan VA Posts: 633	Yes, definitely try different slugs, my Rem 870 shoots Winchester Supremes very good but will not shoot the lighter jacketed slugs worth a hoot! __________________ Do not argue with an idiot. He will drag you down to his level and beat you with experience.--Mark Twain "I have opinions of my own 'strong opinions' but I don't always agree with them."--George Bush

August 30, 2010, 09:27 AM	#2
Dave McC Staff In Memoriam Join Date: October 13, 1999 Location: Columbia, Md, USA Posts: 8,811	When pump guns shoot like that, something is usually loose. Make sure the barrel is tight to the action, make sure the scope and mounts are tightened and Loctited,etc. And after you check, have someone else try a group to eliminate the human factor. Benchtesting really brings out the recoil mule.

August 30, 2010, 09:43 AM	#3
hogdogs Staff In Memoriam Join Date: October 31, 2007 Location: Western Florida panhandle Posts: 11,069	Are you using some super high quality rings? When the scope stop came off one of my air rifles on a diller hunt, I had to retorque the dove tail joint connection as the scope was slipping rearward each shot. By the time I was home, I had severely bent the screw and ruined the scope rings as well as the opposite side "tab" that bites the other side of dovetail. Brent

August 30, 2010, 09:56 AM	#4
Sig_Dude Senior Member Join Date: June 25, 2010 Location: Southeast PA Posts: 115	I am using Leuopold low-mount rings...they are built like a tank. The way I install my scopes is as follows: I have a piece of 1.000" ground rod with a handle on it. I mount the lower ring halves to the pic rail, red Loctite them and torque them up to spec with my Snap-On in-lb wrench. I then lay in the 1" ground stock and install the upper rings over that...so the ground rod is where the scope would be. I apply some Wheeler Engineering lapping compound to the rod and start working it. When working it becomes easy, I tighten down the upper halves a little more. Do this for a while, then take apart to inspect. Make SURE you mark the upper halves and even the screws so they can go back where they came from. You will note that some off the pain/coating is gone from the inside of the rings. This shows your effective contact area. I then re-install the rod and work the lapping compound some more...repeating the aforementioned steps until I have zero paint left i.e. 100% contact. I then stiwth to a higher grit compound and really polish those ring ID's in. When I'm done, the rings look beautiful. I then install the scope with red Loctite and spec-torque the upper screws. The scope will NOT move throughout a lifetime...it simply won't. By the way, do not worry about using red Loctite...if you ever have to remove a "red" screw, simply touch the tip of a soldering iron to the screw head for a few moments and then they will back right out. Anyway, I am certain the scope is mounted right, maybe the barrel is in fact lose. Thanks for the heads-up!

August 30, 2010, 10:59 AM	#5
hogdogs Staff In Memoriam Join Date: October 31, 2007 Location: Western Florida panhandle Posts: 11,069	YEP!!! Sounds like it ain't a loose scope... rule out that possibility! Brent

August 30, 2010, 12:09 PM	#6
Doyle Senior Member Join Date: June 20, 2007 Location: Rainbow City, Alabama Posts: 7,167	Try a different brand of slugs. I've said MANY times on this forum - slug guns are notorious for perferring one particular brand of slugs and hating another.