Smooth rifle shoots over 2 inches high from a sandbag rest. Is this normal?

[Dennis Glazener]

I went out this morning to see if my smooth rifle (20 bore, 38 inch bbl) still pattern's low after putting the sights on it. I had guessed how much to file off the front sight. I had the target at 30 yards where I wanted the shot patterned centered. Since someone here suggested regulating the sights with a round ball then see if the shot patterned there that is what I tried. The first three shots were shot with the gun on sandbags fore and aft. The first three shots were dead on as far as elevation/wind-age was concerned. I was very pleased. I shot the next three offhand same load, same distance. These printed at least 2 or 3 inches low (no ruler with me). I was shooting 65 grains of fffg Goex with 015 patching and Lee High Valley lube.

I then shot 3 #8 shot loads off hand and they too printed about 2 or 3 inches low. I guess I will file the front sight down to have it print dead on with shot and ball but I was curious if this is normal. Guess I should always shoot off hand or aim high!

I shot one load of #6 shot (don't have much of that) and it printed exactly like the #8's. For shot I was shooting 65 grains of 3F Goex with about 1 oz of shot. I say about because my shot flask throws between 3/4 and 7/8 of shot and I found that the Lehigh lube's plastic cap held just a little more probably around 1 oz and I felt that few extra shot might be the difference in eating turkey and eating chicken!
Dennis

[bs2]

If your sand bags are hard, it is like shooting off a bare board. Shots will be high, pad the board and shots will be lower.

Just a thought!

Bruce

[Daryl]

Dennis - it is normal for shot to shoot lower than ball.  This happened back in 1850 with heavy breeches on doubles and singles and happens with them today as well.

The normal 20 bore shot charge, say, 1oz.  or 437.5gr. for a 20 bore, is well in excess of 100gr. heavier than a ball at somewhere betwen 300 and 320gr. depending on the size used.
 

[Dennis Glazener]

Dennis - it is normal for shot to shoot lower than ball.  This happened back in 1850 with heavy breeches on doubles and singles and happens with them today as well.

The normal 20 bore shot charge, say, 1oz.  or 437.5gr. for a 20 bore, is well in excess of 100gr. heavier than a ball at somewhere betwen 300 and 320gr. depending on the size used.
 

Thanks Daryl, I don't think that was the case. Before I fired the shot loads I was shooting round ball. The first three round balls were dead on, I was shooting from my benchrest tripod rest with a hard sand bag in the front and a rabbit ear sand bag in the rear. I then shot 6 round balls all same load and all six was roughly 2.5 inches lower than the benchrest shots.

Then I changed to shot loads, offhand and found them to center low also. Maybe not quite as bad as the round ball but low anyway.

I filed about .060 thousandths off the front sight (shooting was 30 yards) and I am going turkey hunting 0 dark hundred in the morning. Hope I guess right at how much to take off! After I hunt I will pattern the loads again.

Dennis

[Daryl]

0 dark ugly is a nasty time to go hunting - but necerssary sometimes.

Shooting off bags while not holding on to the gun with the 'other' hand as if offhand shooting, resting the back of that hand on the bags, will give false elevation impact.

[smylee grouch]

I had almost the same thing happen so i shot a rifle off the same setup both with hand held forarm and no hand holding forarm and yep she printed high with no hold on the forarm.    Gary

[Leatherbelly]

...and what bs2 said. If you are grouping good off hand,even a little bit low, there's somethin' amiss with your bench rest set up making you shoot high. Lots more variables off the bench.

[Pete G.]

The point where the fore end is supported can change POI also. Also a hard rest can cause the rifle to recoil away from the support. try padding the rest and experiment with different point of support. If worst come to worst, just accept that it shoots to a different POI from rest, and use a stick on aiming point for your load development. As long as she shoots where she looks while hand held, everything will be OK.

BTW what size groups are you getting? If you can tell that you have a 2" change your groups must be pretty good. I have contemplated building a smooth rifle, but always shied away because I wasn't sure it would be accurate enough for me.

[Daryl]

Pete- finding a good load for a smoothbore is the smae as finding a good load for a rifle or shotgun. It involves changing the powder charges, sometimes granulations with differing patch materials or thicknesses and ball sizes.

A lot of very poor shooting is done with smoothbores and round balls because people fail to realize they just can't pick a nice light powder charge along with an easy loading ball and patch combination and make the gun shoot well with it.

Shooting & getting good accuracy at 25 yards is a lot different with a smoothbore than shooting at 50 or 60 yards, just as it is with  rifle.  You will need some load development - I am still working on a good 'longer' range load for my 20 bore.  If I don't get sloppy and pull a shot (only a single sight), I can get a 1" group at 25 yards with it using 3 drams of 2f, but at 50 yards, that 'group' expands to 4 1/2" or 5".  I need to do some more work with it at 50 yards to reduce that grouping capability.  On most steel targets (large), it does wonderfully out to 60 or 70 yards.  I have used it on the trail walk many times and have increased the powder charge to 100 and 115 grs for the longer range targets.  I hit better with the increased powder charges at 90 to 110 yard ranges.  Whether it is shooting more accurately with heavier charges (more likely) or the reduction in elevation from higher velocity is making hitting easier, I'm not sure. I suspect, as Dan Pharris found in his smooth .50, that more powder is needed for longer range acceptable accuracy than many realize.  His 50 requires something like 100gr. 3f to shoot into 3" or a bit better at 50 yards.  My 12 bore double ctg. shotgun, reduced to 26" of barrels made 8" groups at 100 yards off the bags. It seemed I was able to hold 10"-12" offhand, with repeated rights and lefts at that range on a 12" plate.  The powder charges for that grouping were 150gr. and 190gr.  With lighter 110gr. loads, it would not stay on a 100 yard target for 6 shots, 3 from each barrel, yet would almost hold the black with the heavy charges.  This says/means something.

[northmn]

I found differences in bench shooting for fullstock Ml's such that I used to spend time sighting my offhand rifles in off hand.  It took a bit of shooting and one kind of got where you called sight in the center of a group, but surprisingly it worked wuite well for me as I got where I could "call the shots" so to speak.  Offhand rifles did not generally shoot the same off of X sticks.  For shotguns I used the same principle and would place a target on a patterning board and try to shoot at it as a flying target.  Had a S/S double that I got from a sporting goods store and retraded as the one barrel was horribly off as in half a pattern to the side at 30 yards.  In other words sight em in and shoot them as you use them.

DP

[Dennis Glazener]

Well I was in the woods set-up by 5:45AM, it was in the 30's so my hands were cold but thankfully I work my heavy socks/boots/bibb's but the thin camo gloves didn't help a bit! Heard plenty of birds starting around 6:00. Had been working with one for about 15 minutes, he didn't seem to want to come in closer than about a hundred yards then he started getting closer. Then I hit a wrong note on the 50+ year old box call, sounded like a screech owl! He lost all love interest and I guess he is still running! Guess the others ran with him since I didn't hear another gobble!

Later I shot the 20 ga with the same load I used earlier but now it seems to be shooting a little high but it still managed to put a couple of #6 shot in the kill area of the target at 28 yards. I think I will go back Monday and before I leave I will try messing around with the load to see if I can get a tighter pattern.

Thanks for the help,
Dennis
 

[Dennis Glazener]

BTW what size groups are you getting? If you can tell that you have a 2" change your groups must be pretty good. I have contemplated building a smooth rifle, but always shied away because I wasn't sure it would be accurate enough for me.

The first three shots from a rest at 30 yards were about 3 inches horizontal spread the 2nd and 3rd shot were about and inch center to center. Off hand was another story and we don't need to tell that!

This is the first smooth bore I have ever built and I believe it will be the perfect hunting gun for me. I don't hunt a lot and what hunting I do probably would be at a maximum of 50 yards I believe this smooth rifle will be as good as my .54 cal rifle at that distance. It does kick considerably more than the .54.

I used to be a big quail hunter and I would love to use this gun on quail, if there were any quail around anymore!
Dennis

[Daryl]

Changes in powder temperature will also give an elevation change.  Part of the mystique of the smoothbore with shot or ball, is learning how high to hold your eye above the breech when sighting. Normally shotgun shooting, is a point and shoot secenario, without actually aiming, but wiht flintlocks something more deliberate might give more hits due to lock time.

[G-Man]

Might be just me, but when shooting off a bench I find it really hard to hold a longrifle the same way I do when shooting offhand unless I really make a conscious effort to think about it and adjust where my cheek sits on every shot.  Specifically, I tend to shoot lower from a bench as I tend to not put my cheek down as low onto the cheekpiece- so what happens is that when I shoot from a bench, my line of sight is a bit higher so I have to drop the front of the barrel a bit more to line up the front sight, which causes the lower impact.  So when sighting in a rifle I have to get it to shoot centered right to left and within about 2-3 inches low on elevation while shooting from a rest, then switch to offhand before filing any more off the front sight.

Guy

[Daryl]

To shoot off a bench and get the same results as shooting offhand, I find the bags or rest must be quite high -or rtehr the shotoing postion is higher than normal for bench shooting.  The design of our stocks requires some of this height as well, but sitting high (high, adjustable seat) compared to the bench top height is also necessary.  The postion and gun hold must be hard - modern BR techniques don't work well.