point of impact issue driving me crazy with revolver

[JacobusRex]

I've got a SP101 with 3" barrel that shoots on at 25 yards with Federal .38 158gr LRN factory ammo. I'd like to duplicate that load to save money but with .357 cases because I have a ton of them.

The Federal .38 factory load averages about 680 fps out of my 3" barrel. My reload is .357 cases, 158gr SWC and 4.0 grains of Trailboss. Winchester standard primer and a fairly heavy Lee factory crimp. Average velocity of about 682 fps.

You'd think the two would shoot close together but the reload shoots a good 6" lower than the factory load at 25 yards.

Maybe the issue is me??? My eyes aren't what they use to be. However, others seem to also shoot low vs the factory load.

Primers, powder, crimp???? Any ideas?

[Electrod47]

Pick a better powder....and start walking up your velocity to 850fps and see what that does. Better powder? Unique would be a good place to start. Lots of other fast powders that are applicable. I doubt your using a SP101 for Cowboy Action. My 2C's

[ACC]

Yes it's you. Not me but you. Different shaped bullet different hitting spot.

ACC

[44MAG#1]

Deep seat the 158 gr SWC to the same OAL as the specs for that bullet in the 38 Special cases and use 38 Special data.
Just lightly crimp over the front drive band and try it.

[Rapier]

With a handgun a difference in velocity causes impact point differences. Slower projectile impacts higher, more time in barrel, recoil, etc.

[WRideout]

I have a Spanish copy of a S&W revolver in 32-20. I tried a variety of different boolits, donated by kindly members here. It turned out that it likes the Lee 100 gr .30 cal boolit sized .313". Then I started chasing powders. I was willing to accept mediocre accuracy for a while, but began to look for better performance. Unique almost always worked for me in other calibers, so I started with that, then went to Bullseye, Promo (AKA Red Dot) and a few others. All of them were too high, too low, or just lousy accuracy. In frustration I looked up rifle loads in an old Lyman cast bullet handbook.

I have one can of SR4759 which is old as the hills; a starting rifle load is around 8 gr. I loaded a series with the Lee boolit going from 5 to 6 gr 4759 in half grain increments. Behold, 5.5 gr of 4759 under the 100 grain boolit yielded fully acceptable accuracy, and shot just a tad low at five yards. It is conventional wisdom that using slower powders without much pressure leads to a dirty gun. However, the powder left behind with this load remains chunky, not sooty, and oddly the graphite coating is burned off leaving particles that look like corn pollen. They just shake out of the case.

I realize that this is not exactly what the op was looking for, but I hoped to describe a process that worked for me. Sometimes conventional wisdom has to go out the window in favor of pragmatic results.

Wayne

[Rich/WIS]

My experience with revolvers seems to indicate that impact is inverse to velocity, faster loads shoot lower than low velocity load. Always figured this was due to shorter barrel time and thus the faster bullet exited with less barrel rise. Given your velocities are essentially the same your results are puzzling.

[mdi]

I believe I would scrap the load data you are using and start all over with a new load workup. Looks like you changed three factors from the factory load; different bullet, different case and different powder. All can have an effect on load performance. I use a lot of Universal powder in my 38/357 revolvers and when I started reloading 38 Special with 158 gr LRN I used a Bullseye almost exclusively...

[Der Gebirgsjager]

Frankly, I'd be surprised if using a .38 Spec. load in a .357 mag. case would get you the same results. I think the advice from several to start over is good. Personally, I'm not in love with the 158 gr. LRN. Why not switch to 148 gr. wadcutters, which are renowned for their accuracy? They cast great, or you can buy them in bulk. Since target shooting seems to be your activity, they make nice round holes for scoring. Bullseye, Unique, and Accurate #5 are good.

DG

[Bazoo]

Using a powder like bullseye or titegroup will raise the point of impact, as it has a sharper recoil. Figuring out the powder type that is in the cartridges you like is the key to duplicating a similar POI. Likely the factory loads don't use canister grade powder, but do use something similar to bullseye.

[rintinglen]

Try 3.9 grains of Bullseye, or titegroup, or 4.2 grains of WW231 or HP38, in your 357 brass.

[Land Owner]

I applaud your ownership and use of a Ruger's SP101. I have shot many boolit types and decided in my personal protection SP101 to use 144 gr., MEHA 360-146 SWC HP's, over a variety of powders. I have not finished my testing but really like shooting the gun.

With a rubber Houge monogrip, the gun fits my sweaty basketball palming hand. It's weight and shape resist recoil (for me) instead of delivering that to the wrist. I practice shooting it a lot to loosen it up a little bit, as I got it new, straight off of the Ruger assembly line, as a replacement for a former 101, which I ran over with a bushhog - but that's another story https://castboolits.gunloads.com/sho...ht=ruger+sp101.

I took it apart, polished and smoothed the double-action trigger and trigger parts from 12-pounds (+/- factory) to 6-pounds, which I expect long-term wear to reduce a little more. It is a sweet set up and I carry it concealed every day I leave the house.

[MT Gianni]

At 680 fps you surely don't need a heavy crimp. Make a minimal crimp and put it in the crimp groove. Change powder or amounts until you see bullet movement. If you're shooting offhand for accuracy testing and load printing you're wasting your time.

[44MAG#1]

At 680 fps you surely don't need a heavy crimp. Make a minimal crimp and put it in the crimp groove. Change powder or amounts until you see bullet movement. If you're shooting offhand for accuracy testing and load printing you're wasting your time.

Is he really wasting his time if he does the vast, vast, vast majority of his shooting offhand.
Now if he is addicted to benchrest shooting maybe so.
If you can't shoot well enough to sight your gun offhand then much more practice is needed in a bad way.

[Dusty Bannister]

Shooting from a rest does eliminate many of the variables. I spent a lot of time weighing charges for a friend to do test loads in his handgun. He shot them off hand, said they all shot fine. Proved absolutely nothing without carefully shot targets to examine.

The point I would try to make is that shooting from a rest does reduce the human element and if a shot does go out of the group, it is most likely the bullet and not the shooter.

[44MAG#1]

Shooting from a rest does eliminate many of the variables. I spent a lot of time weighing charges for a friend to do test loads in his handgun. He shot them off hand, said they all shot fine. Proved absolutely nothing without carefully shot targets to examine.

The point I would try to make is that shooting from a rest does reduce the human element and if a shot does go out of the group, it is most likely the bullet and not the shooter.

If one can call his shots he knows if something is rotten in Denmark.
Goes back to what I have said about most Ive seen shooting handguns.

[Dusty Bannister]

If one can call his shots he knows if something is rotten in Denmark.
Goes back to what I have said about most Ive seen shooting handguns.

Referring back to post #1. It has been stated that there might be a shooter error. First post and a long time member. Unless you personally know this OP don't you think you are assuming an awfully lot about shooting ability. It seems he has a valid question and is looking for an answer to his problem.

[44MAG#1]

Referring back to post #1. It has been stated that there might be a shooter error. First post and a long time member. Unless you personally know this OP don't you think you are assuming an awfully lot about shooting ability. It seems he has a valid question and is looking for an answer to his problem.

I am not assuming anything. If a given load shoots POI on POA then another load doesn't one should be able to tell that offhand if that person can shoot well
If a load doesn't and one wants to use that load adjust the sights for that load. If fixed sights hold to compensate for it or experiment to find a load, if possible, to hit POI on POA.
Still if one can shoot well he can do it offhand. The OP needs to experiment to find "the load". As I have said on numerous posts experimentation is the key to success.
Even sun on the sights can play the devil with POI vs POA.
But one has to be good enough offhand to know.
The OP may be a top shot. I don't know.
Experiment, experiment, experiment.

[MT Gianni]

Is he really wasting his time if he does the vast, vast, vast majority of his shooting offhand.
Now if he is addicted to benchrest shooting maybe so.
If you can't shoot well enough to sight your gun offhand then much more practice is needed in a bad way.

I find in almost all shooters, groups shrink when shot from a rest @ 25 yards minimum distance. If yours don't change I commend you.

[44MAG#1]

I find in almost all shooters, groups shrink when shot from a rest @ 25 yards minimum distance. If yours don't change I commend you.

I DID NOT say groups won't shrink when shot off a benchrest versus shot offhand.
A good shooter will shoot groups offhand that will be good enough that one can sight in offhand.
If one can't then much,much, much, much more work is needed.
Can't you sight in offhand? I can.
AND, I don't shoot as well now as I use to due to being 70 and shooting far less now.