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by TEX
Sun May 21, 2006 11:52 pm
Forum: General Gun, Shooting & Equipment Discussion
Topic: Chronographing 38spl 135gr GDHP for Short Barrels
Replies: 5
Views: 1028

Thought this might interest anyone whom has a 38 revolver and was considering the Speer Gold Dot 135g +P or the 125g +P. I was testing defensive loads for my wife’s S&W Model-10 with fixed sights. She hates magnums and hates autos, so this is basically what she is stuck with and has grown use to shooting over the years. I tested a number of different 38-Special defensive and targets loads to match up a decent defensive load and practice load that would hit very near the point of aim. Because the Model-10 has fixed sights adjusting for vertical or horizontal deviation was not an option. In defensive loads, I tested Corbon’s 125g +P DPX round, Winchester 125g +P Silvertips, Remington Golden Saber 125g +P, Federal Hydrashok 125g +P, and both the 125g and 135g +P Speer Gold Dot rounds. It is my understanding that the 135g Gold Dot was specifically made for short 2� barrels, but I figured that if that was the case, then it should show pretty good velocity and low muzzle flash in a 4-inch barrel – I was right.

When I shoot for groups, I use a target with 10-mm grid squares. I measure the average distance of deviation from the vertical and horizontal lines intersecting the point of aim, to arrive at the group center, and then average the distance from each of the 10 shots to the group’s center. If any one shot is 200% or more of that average, I throw it out as a flyer, and then recalculate the average. So if you see a measurement such as 3/4“ associated with the round, it means that at 15-yards in a very slow and careful off hand shot, the rounds hit, on average, that far away from the groups center. I know most folks measure the widest stretch between the two farthest rounds, but that has never made much sense to me. You could have 9 rounds that made one big clover leaf and then one stray 2-inches away from the clover leaf and it would be called a 2-inch group, which would not exactly reflect just how tight a group the round was capable of making.

I did not chronograph all of the rounds. Just the two I finally decided on as the best, which both happened to be the Speer Gold Dots (125g +P & 135g +P). They both hit about the same spot (maybe 1/4� apart) and only hit about 1/2� to 1� above the point of aim and 1/4� to the left. I figured that this was just fine as when firing DAO rapidly, you would probably pull the rounds down and to the right ever so slightly. Also, this difference would all but disappear at fighting distances of 7-yards and under.

The 125g Gold Dot does not have as wide open a hollow point as the 135g. At 15-yards the average distance from group center for 10-rounds per weight, was 3/4“ on both loads. Here is the kicker. The velocity difference between the two different loads was only 2.2 fps. The choice seemed obvious- the 135g Gold Dot. The fact that it is heavier should mean it would penetrate deeper, but this may be offset by the wide nose, which I assume would open a little faster than the 125g bullet. This would cause it to offer resistance earlier in its track. Either way the 135g has more energy – if that matters? I really wish I had a 2� to test it from to see how much additional velocity the extra 2-inches of the Model-10 provided. The Magtech 125g FMJ turned out to hit on the same vertical line as both Gold Dot loads, and only 1/2“ – 1� lower - at 15 yards. Winchester White Box 138g FMJ, Sellier & Bellot 158g FMJ, and Blazer 158g LRN all hit on nearly the same vertical line and none were more than 1.25� from the impact of the Gold Dots. Now if I can just find a place to get the Magtech really cheap.

Defensive Loads

Federal Hydrashok 125g +P (7/8�)
Speer Gold Dot 135g +P (3/4�) Average speed 948.6 fps (max deviation 27 fps) 10-rounds
Speer Gold Dot 125g +P (3/4�) Average speed 950.8 fps (max deviation 34 fps) 10-rounds
Remington Golden Saber 125g +P (7/8�)
CorBon DPX 125g +P (3/4�)
Winchester Silvertip 125g +P (7/8�)

Practice/Target Loads

Blazer Aluminum Case 158g LRN (1�)
Fiocchi 158g FML (1�)
Sellier & Bellot 158g FMJ (1�)
Magtech 158g LRN (7/8�)
Magtech 125g FMJ (7/8�)
Winchester White Box 138g FMJ (3/4�)
Federal American Eagle 130g FMJ (3/4�)

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