20 ga. USH accuracy problems-help!

[sliceman]

I bought a new 20 ga USH this year largely on the basis of glowing accuracy reports and reduced recoil, now that 20 ga ammo with some serious punch is available. To say I am disapointed would be an understatement. First, I am not new to shotgun slug shooting. With my BPS 12 ga I can get 1-2" groups at 100 yds with Rem core-lokts, using a lead sled(no lead) and the hard-hold method advocated by Randy Fritz on the Tar-Hunt Lightfield site. Essentially my front hand (gripping the USH) is resting on the front of the lead sled pulling down and back, with the butt firmly against my shoulder- a very stable rest.

I have checked the scope rail, made sure it is properly cleared in front, and have tried 2 proven scopes(both VX-3's 2.5-8X) with 3 different steel mounts(currently Warne Maxima).

Results at 100 yds(5 shot groups):
Fed Barnes Expander 1450fps      5.2" (av vel 1328fps@13 ft)
Fed Barnes Ex 1900fps(3")          over 7"
Fed Barnes TMZ 1900fps            over 12"(some shots never hit the target)
Rem Core-Lokt 1900 fps             over 7" (av vel 1825fps@13ft)
Rem Copper-Solids 1500 fps        2.4" (the best of the bunch)(av vel 1346fps@13ft)
Win Part Gold 1900fps                6.5" and 6.0"
Win Plat Tip 1700 fps                 3.7"(2nd best)(av vel 1690fps@13ft-closest to published vel)
Hornady SST 1900 fps                6.5" (av vel 1697fps@13ft)

Although the copper solids are accurate enough for hunting, they run out of enough energy by 100 yds(as av muzzle vel by my chrony is only 1350fps). I was looking for this to be a 150 yd weapon with the faster 1900fps ammo. I don't think the Win Plat Tips would be accurate enough at 150yds. Lightfields are not available in this area of Canada.Any help or suggestions would be appreciated.

[sliceman]

Sorry, the Fed 1450 fps ammo were Hydra-Shoks, not Barnes Expanders.

[cwlongshot]

Well,
 Sorry your having accuracy problems. H&R may help you as I know they have a min accuracy requirement. Don't know what it is....

Anyhow, short of that. Obviously you have shot enough different ammo that if there was something out there that it would like you would likely have found it.

So its now time for you to look at the firearm. The FAQ's can offer much, once you read thru and find what applies. We could help a bit more, but simply the size of the group doesn't off enough, sans to show there is a problem.
 
Lets start with the basics, Hows the trigger? I know you said your shooting from a led-sled. This is an AIDE NOT a crutch. Definitely NOT a cure all. You, as the shooter can still cause problems that will effect your overall accuracy ability. Have you tried shooting without the for-end? Have you tried changing the location of the front support? Have you cleaned the latch and are you careful of how you close the action? Also, how dose the muzzle look? Maybe chopping a bit and re-crowning. Pillar bed and float the for-end also almost never hurts. If nothing else it will all but eliminate the issues with the for-end and that's huge with handis.

  Lastly, do be quite so hung up on velocity. If you have an accurate load, its pretty easy to work out the trajectory for longer hits. Velocity and energy charts almost never figure in the diameter of the projectile. We all know its much better killing ability. The 20 Ga ain't huge as shotguns go, but compared to a rifle caliber you would normally use for deer has to really do something to reach the 20's diameter before its fired.

Hope this offers some help, it certainly gives you some options.

CW

[MI.sabot]

Been there and I feel your pain.

I bought a 12 ga. USH a few years ago.  At the same time I bought a 20 ga. USH for my son.
As his interests turned to things other than hunting, I decided there was no longer a need for 2 slug guns in the arsenal and decided I would keep the better shooting of the two.  I was really hoping the 20 ga would be the winner because of the lighter weight and reduced re-coil.

Off to the range with a $100 of various slugs only to find that I was having trouble keeping it on the paper at 50-75 yds.  Went back to the very reputable gun shop where the gun was purchased to check the bore sighting and the mounts.  Sent the scope back to Leupold to be checked out.  Everything gun-wise and scope-wise was said to be A-OK.  Re-mounted, re-bore sighted and returned to the range.   Results were better, not great, but nowhere near as accurate as my 12 ga. has been from day 1.

It was a good excuse to trade the 20 ga. in for a muzzleloader which has turned out to be my favorite fire-arm.

Your experience and mine are not the only disappointments I've picked up on in some of these forums.  Funny thing is I only read about these problems in the 20 ga. eventhough there are many 20 ga. USH shooters who seemingly have excellent results with theirs. There seems to be a common flaw somewhere that I believe is attributable to something other than the shooter or the ammunition.

[PHATINJUN]

Before I panicked and started worrying that it's the gun I would try shooting some Buckhammer or some Hastings slugs .If the rem copper solids are 2.4 at 100 thats not a bad start as those seem to work well for others. I'm not a firm believer in the lead sled deal and think they may be the cause of some issues . Try some bags and then work from the FAQ's on the accuracy issues. But I would stay away from the screamers til you figure out whats up.Kurt

[stormsearch]

Slice - I just posted an update to my USH 20 and see this thread right next to mine.  Try thoroughly cleaning your gun (squeaky clean).  Every 3 - 5 shells, I have to clean mine otherwise accuracy is gone.  It sucks with a shotgun, but mine it was a must.  Check my results.

stormsearch

[sliceman]

Gentlemen, thank you for your replies.

cwlongshot, my trigger is as supplied, but not bad, measured it at 4.25 lbs. I have not shot it without the forearm-you would have to hold the barrel,and shooting modified free recoil like a centerfire doesn't work well with shotguns. In terms of changing where I hold the forearm- my hand is holding the forearm just behind the front sling stud. and that hand is resting on the front rest of the leadsled. It's where I would hold it while taking a shot hunting. The latch has been cleaned and closes well, so I do not think this is the problem. The muzzle appears fine, all lands and grooves seem to be the same depth.

PHATINJUN, I will try buckhammers if I can get them, Hastings are not available in this area.

Stormsearch, I confess I have not cleaned my barrel every 5 shots, and will try it. However,I noticed even within the first 5 shots through the gun that the dispersion was way more than I would expect.                                                                                                                                                                                                                                                                                      Thanks again for your suggestions.
 

[cwlongshot]

 Don't underestimate the differences little things can make!!! Try it with out the for-end, its only a 20, just shoot it. Hold the receiver, hands off the barrel all together. I am well aware its a shotgun, but don't forget, its a SLUG gun. Its being shot and handled just as if it where a rifle. I gotta say, for-ends and the firearms latch, account for the lions share of the problems associated with accuracy problems.

 Snapping the action closed concisely and consistently does make a difference. The trigger @ 4.25# isn't bad as long as its clean. Be sure the gun suprises you when kit goes off, with every shot. Its very easy to flinch with recoil or with anticipation. Even with the lead shed. Your mention the need of the lead sled along with your reminding me its a shotgun kinda says you may be "worried" about recoil.
 Please do not take this as a slight, it certainly is not. Its just an assessment based on what I am reading here. This CAN help you if you choose to head the advice. Most everything I am offering here is also in the FAQ's.

I also have the USH, both in a 12 and a 20, the 12 is more accurate, but the 20 is everybit as accurate as I need it to be.

 Good luck,
 CW

[sliceman]

cwlongshot, thanks for the suggestion, I will try it without the forend. I don't think I have a problem with flinching as I had a misfire with one partition gold, and the gun did not move off the target at all.

[d_hiker]

One of the things that I have found is that never assume that the scope rail is on tight and correct unless you have mounted it yourself.  It doesn't take very much movement in the mount and scope to make a difference.  I use a piece of 400 grit sand paper wrapped around the barrel at the mount location (grit facing away from the barrel  ).  Then I place the mount on the sand paper and gentley move it back and forth a few times then look at it.  If it is making full contact with the breech end of the barrel, then it will be shiney evenly across its surface.  Then I place a small amount of blue Loc-Tite on the bottom of the mount where it makes contact with the barrel to act as a bedding material.  Using the blue Loc-Tite on the mount screws, I then attach the scope rail (base) to the barrel. 

With my 20ga USH (thanks Jay) it shoots most anything well at 50 yards.  The cheapo Remington Slugger printed about a 1.5" 3 shot group.  The cheap Winchester slugs were about a 2.5" group.  I tried a few other cheaper slugs, with results ranging from the 1.5" group to about a 3.5" group from some Breneke KO slugs ($1.99 a box).  I then tried the Remington BuckHammers, 2 3/4".  At 50 yds three shots were touching.  Then I moved the target to 100 yards.  All of the cheap slug groups opened up.  The Winchester slugs were key-holeing with a 6" group.  Breneke KO were about a 12" group.  The BuckHammers were about 1.5".  The BuckHammers do kick but I never noticed it during the hunt.  In 20ga I don't believe there was much ballistic difference between the 2 3/4" and the 3", just a couple dollars more for the 3".  They are advertised are 1550fps with a 1oz slug.  At 100+yards the BuckHammer did a number on my buck last year.  If my shots were only going to be in the 30 to 60 yard range, I would use the Remington Sluggers, cheap and effective.  But for the 100 yard shots, I want my BuckHammer.  While shooting the groups I used my portable shooting table with a shooting bag placed right up against the trigger guard.

I hope that this might help.  Remounting the scope rail on my .22 Hornet tightened the groups with no other changes.

[sliceman]

d_hiker, I looked at the  rail, tried to take it off to re-mount it with loc-tite, and could not budge the 3 screws at the rear. I did loc-tite the front elevating screw with the rail at 0.015" clearance.

[d_hiker]

It sounds like you are working this through in the right direction.  A couple of times I have heated the screws a bit to make them easier to come out.  Actually they had been secured with some type of adhesive or Loc-Tite.  I used a soldering iron and placed it on the screw head briefly.  A heat gun or hair dryer should work also.  So far I haven't broke a screw or messed up the head too bad.

[quickdtoo]

There's a topic in the FAQs and Help with a bunch of suggestions for scope screw removal help and others on mounting the base and scopes. 

Tim

[jdp29]

I have struggled w/ accuracy in my 12ga USH.  Can you guys go into more detail about the "latch" and how that might affect the shot?

Thank You

[sliceman]

Just an update. I got back to the range yesterday with WW Platinum Tips(these were the 2nd most accurate load in initial testing, but their ave muzzle velocity(1687fps) was much better than Copper Solids(1346fps) and therefore better energy at 100-125 yds). With a clean barrel, using a Caldwell rock front rest and rabbit ear rear bag,pulling down on the rear portion of the forearm(front sling swivel removed) I got a 4.0" 5-shot group, although 4 shots were 1.9"(100yds). The group was vertically strung, and was only1.1" horizontally-encouraging. I then adjusted the scope and tried a more natural hold, ie the gun in my left hand, with that hand resting on the front rest, same back rest-not quite as steady but OK. I got a 2.7" 5-shot and 1.9" 4-shot group. This should be fine to 125 yds, with lots of energy. Thanks again for everyone's suggestions.

[d_hiker]

That sounds good enough to put meat in the freezer.