Shooting different boolit weights in .38 Special with fixed sights?

[FergusonTO35]

Hey guys. All my .38 Special wheelguns have fixed sights and are dead on with 158 grain boolits, their favorite load is 5.7 grains of Accurate #5 for 870 fps out of a 4" tube. I am perfectly satisfied with the 158's but would prefer to shoot lighter boolits for practice to save lead. My guns are accurate with the lightweight slugs of 125 and 140 grains but print low with them. My understanding of the way sight regulation works is that the heavier boolits produce more recoil, causing the muzzle to rise more and the POI to rise. Conversely a lighter boolit creates less recoil and muzzle rise, meaning a lower POI if the same gun and sights are used. Is this correct? If I raised the velocity of my lightweight boolits, creating more recoil, would this raise the POI? Is it feasible to create a light boolit load with the same POI as a heavier boolit? Thanks!

[fecmech]

Actually just the opposite will happen as your barrel time will be less. I think this is a case of "you can't get there from here". Using my K38 with a dot sight I need 4 clicks of elevation difference between my 158@900 fps and my 120@ 1020fps at 50 yds. One thing you could do but probably don't want to, is file the front sight down so that you use a "6 O clock hold" with the 158's and "center hold" with the 125's.

[bobthenailer]

For fixed sight guns as a general rule

point of impact can be lowered with a lighter bullet.

point of impact can be raised with a heavyer bullet.

POI can also be vaired somewhat by higher or lower velocity.

[captaint]

Plus one - what Bob said. He is correct. Mike

[bruce drake]

Bob Nailed It.

Bruce

[GabbyM]

As stated. Slow down the 125's.
Even with a faster powder like Bullseye or 700x they will shoot higher when run about 800 fps.
With your AA#5 powder. When you drop the charge down to where the 125's are shooting the same velocity as the 158's they will be close to same POI. Trick is they don't start hitting to the left. Which so far is what my reduced laod 148gr wad cutters do.

[FergusonTO35]

Hmm. My 158's are running 870 fps out of a 4" barrel. So, if I create a load with the same velocity and a lighter boolit that should be really close?

[44MAG#1]

Here i am being a simpleton.
As long as you are practicing what does it matter is they print low?
Shoot a couple shots, see how low, and paste a bullseye high enough to get them in your main bullseye.
All you are concerned with is being able to group your shots.
I couldn't care less where they are grouping as long as it is well on the paper.
Unless you can group a series of shots well you can't shoot well no matter where they group.
Your business ammo is the 158's that shoot close to the sights right?
So why care about practice ammo as long as it shoots well along with your good grouping capability?

[BCRider]

Hmm. My 158's are running 870 fps out of a 4" barrel. So, if I create a load with the same velocity and a lighter boolit that should be really close?

Almost but not quite. I've done this and found that they have to slow down even more because you don't use as much powder for the lighter bullet the recoil isn't as strong. So it has to slow down even MORE. You'll likely end up shooting the 125's at around 700 fps to get them to print at the same spot as the 158's.

The classic 158gn LRN equivalent for target shooting is the 148gn HBWC powered by 2.7 to 3.2gns of Bullseye. The final load being determined by how they print to your POA. Lower powder level prints higher. That's been a classic bullseye match load for years. Looking around for velocity it seems that they come out the end at around 800fps.

I should add that I tried some 130gn boolits in my Model 10 fixed sight revolver. Despite the light cowboy action loads they still printed low. I could likely get them slower and finally hit at the right spot but by then I might as well be shooting a .22.

In the end you might simply be best off shooting your 125 loads and let them hit low. Just know how far low they hit and go for the grouping. Or do the funky sights thing mentioned where you use a 6 o'clock hold for 158's and direct for 125's.

I hate that idea though. I'd rather buy a few boxes of the 148 HBWC bullets and go with that so they print where expected.

[FergusonTO35]

It's alot to think about for sure. Another question, does barrel length usually affect how sensitive a gun is to boolit weight? I used to have an old Charter Arms snub that seemed to be dead on with anything.

[.22-10-45]

I was shooting cast in a 7 1/2" Colt 2nd. gen. .38 Special S.A.A. few years back. Now with most of my handguns..S&W .22 thru .41Mag., for load development I like to shoot with wrist on sandbags..everything was just fine until I tried it with this Colt! At 25yds.. No matter the load or bullet weight...every shot was low & right..I'm talking just barely hitting botttom R.H. corner of 3' square cardboard backer!
I even tried some heavy 200gr. slugs..this brought POI up..but still 6" low..and 5" right. I was thinking of filing front & turning barrel...
Then the o'l lightbulb flickered on...I loaded it up with 158gr. bullets..and shot it one handed...just like magic, the POI was right on top of front sight..with perfect windage!
I find the POI is to POA when shooting two handed offhand..or sitting with elbows resting on knees...but NO rest shooting with this one!

[gunfan]

FergusonTO35: I don't know quite how to say this, but I think that you will be best served by using the original 158-grain load. While that may not be what you want to hear, I still think that it will probably be best.

The lighter bullets may serve quite well for small game, but for antipersonnel work the 158-grain LSWCHP+P loads will be the best that you can get.

Scott

[rintinglen]

It's alot to think about for sure. Another question, does barrel length usually affect how sensitive a gun is to boolit weight? I used to have an old Charter Arms snub that seemed to be dead on with anything.

I believe it does. Though exactly how it works seems to defy common sense. A 5 inch fixed sight 38 Colt shoots lee 125 grain RNFP pretty close to the Lyman 358-311, after some tinkering. The same loads diverge markedly from my old pencil barrel Smith model 10. My 6 inch M-14-3 shoots them closer, but still farther apart than the colt. I've not got around to trying these out in the snubbies.

[Artful]

Simple solution is to paint/tape on the front sight the hold over for the lighter weight bullet. Then use the top of the blade for 158's and the lower mark on the sight for the 125's.

[Poohgyrr]

Simple solution is to paint/tape on the front sight the hold over for the lighter weight bullet. Then use the top of the blade for 158's and the lower mark on the sight for the 125's.

Sounds like what Elmer Keith and others have done for distance shooting. Kentucky Windage is the idea. It's nice when our normal sight picture works for everything, but things don't always work that way.

[fecmech]

I believe it does. Though exactly how it works seems to defy common sense.
The reason shorter barrels shoot different wts closer is simply "barrel" time and rise. The longer barrel has a longer barrel time to rise in recoil carrying the bullet with it. Heavier bullet = heavier recoil= more barrel rise. Longer barrel= higher bullet exit vs lighter bullet exit.