I need help with ballistics - 38 wadcutter

[Chris_D]

Hi all,

I shoot a model 52 and for the first time this weekend shot in an outdoor match. I learned very quickly that my zero point is much lower (4-5 inches) at 50 yards that it is at 25 yards.

With my 22 and 45, the zero point is the same at both distances.

My current load is:

148 grain HBWC
2.7 grains of bullseye
CCI primer

I was loading at 3.1 grains of bullseye, but based on the advise of others, I dropped that to the current 2.7 grains.

I am wondering if anyone can tell me how to confirm the bullet drop amount. I have seen online ballistics calculators, but frankly I don't know how to use or interpret them yet.

Chris

 

[RGPM1A]

Chris. I ran your load on the following link:

Handloads.Com Ballistic Calculator

I assumed your bullet velocity was 675fps, your sight height was 0.5", and that the BC for the bullet was 0.047 (both from the Hornady manual for a 148 grain HBWC). The calculator did indeed indicate a 5" drop at 50 yards if you zero at 25 yards. However if you sight it in at 50 yards you will be 2.5" high at 25 yards. If you have a red dot sight you might sight at 50 with a center hold and use a 6 o'clock hold at 25 yards.

BTW you couldn't safely increase the velocity high enough to have the same POI at 25 and 50 yards with Bullseye or any powder that Hormady has data for in the manual. FWIW

 

[nightshade2x]

Alot of cast .38 WC's were not designed for 50 yard shooting. At least many of the DEWC's. Some will work better than others but 50 yards is about the limit for a WC design.

Have fun and be safe.
Nightshade2x

 

[TSQUARED]

When I used a S&W 52 for CF bullseye my load was 2.8 gr. Bullseye, Remington 148 gr. LHBWC and Rem 1.5 primer. I hasd the gun sighted in at 50 yards and then had a note pasted onto my shooting box which reminded me how many clicks downward to adjust the sight for 25 yards - the system worked for me. The alternative is to adjust your point of aim - I know several shooters who do just that.

 

[ArchAngelCD]

Either 3.4gr or 3.5gr of W231/HP-38 will shoot POA at both 25 yards and 50 yards.

I agree upping the charge to 3.1gr Bullseye will improve the situation.

 

[HKSmith]

I don't believe there's any way to get a .38 SPL WC bullet to be sighted in at both 25 and 50 yards, regardless of the powder type or charge.

Most bullseye shooters use a six o'clock hold, which means the bullet needs to strike about 2.75 inches high at 25 yards to hit center. The 50 yard (slow fire) target is the same size, but has a larger black - it includes the 8, 9 and 10 rings, whereas the 25 yard (timed and rapid fire) target has a black that only includes the 9 and 10 rings. This means that a six o'clock hold on the 50 yard target is 4.0 inches below the center. This arrangement allows the six o'clock hold to be used at both distances because the bullet is still rising beyond 25 yards and will hit higher on the target at 50 yards. This just happens to work out well for the ballistics of the .38 WC load. If you want to use a center hold at both distances, you'll have to adjust your sights between targets. The gun will actually be sighted in for 80-85 yards when you use the six o'clock hold.

Although it's generally true that a gun will shoot to point of aim at two distances (the first when the bullet is on the way up and crosses the line of sight soon after leaving the muzzle, the second after it's reached maximum height and recrosses the line of sight on its way down), the first point is less than 5 yards from the muzzle when the gun is sighted in at 50 yards with a .38 WC.

 

[Chris_D]

Thanks for all the great information guys. I guess I have a lot more to think about than simply changing the load to resolve this. At the moment, I am favoring the idea of adjusting the sight (Ultra Dot scope).

Chris