just as a heads up, I tried a box of Underwood 38 special +p xtreme defender in my S&W 638 recently and had terrible results. the ammunition was horribly inaccurate and appears to be key holing almost every shot.
I called Underwood and let them know I was having trouble along with the lot number. their response was: "we haven't had any trouble with that ammunition but we will look into it".
-matt
What shape is your your barrel in? Have you shot any lead through it?
Sounds like the same response I got last time I contacted them reference a bad lot.
Best to talk to Kevin Underwood himself.
I have to wonder if the bullets are too small in diameter and not taking to the rifling well.
Quote from: The_Shadow on April 08 2017 08:16:34 AM MDT
I have to wonder if the bullets are too small in diameter and not taking to the rifling well.
That was my first thought.
There has been a problem with this and the Lehigh defense bullets in the past, correct?
Quote from: Intercooler on April 06 2017 03:49:08 PM MDT
What shape is your your barrel in? Have you shot any lead through it?
barrel was clean, only jacketed ammunition fired threw the gun before trying this ammunition.
I do have 5 of these defender cartridges left, perhaps ill pull one down.
-matt
I just pulled a cartridge down and it doesn't appear the bullet is undersized. I measured it at various points and I'm getting .356"-.357" so there is no trouble with diameter.
I haven't ever had trouble with this pistol before and ive shot plenty of different loads over the 6-7 years ive owned it. this gun is very accurate with standard 125gr +p loads.
however I do admit all the loads ive shot have been between 125gr and 158gr so perhaps these pistols have trouble with lighter bullets?
-matt
Did you take a measure of the powder charge weight? Take a picture of the powder?
We need to know these things! LOL :))
I thought about it but I have a hammer style bullet puller and sadly a portion of the powder was lost.
-matt
Quote from: matt85 on April 14 2017 06:05:16 AM MDT
I thought about it but I have a hammer style bullet puller and sadly a portion of the powder was lost.
-matt
Weigh the entire cartridge first. After you pull the bullet, weigh the bullet and empty case. Subtract that weight from the full cartridge, and you should have the power weight.
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What weight bullet? It looks like the Underwood 38 +P XD is 100grains
The longer the bullet, the faster it needs to spin to be stabilized. Length is the factor, not just the weight.
A shorter barreled gun will spin the bullet at a slower RPM than a longer barreled gun with the same rifling twist rate.
If that is the case then those loads would work perfectly out of a longer barrel gun, but not a shorter one.
P.S. Underwood lists that load @ 1300 fps. I doubt that is from a 2" barrel.
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Sounds hot for a .38 Special.
I know this is an old topic but Avoid snake oil bullets. Also, keyholes couldn't possibly a fault of Underwood's, as that usually comes from being spun too slow and a 638 doesn't have much rifling to work with.
Quote from: matt85 on April 14 2017 06:05:16 AM MDT
I thought about it but I have a hammer style bullet puller and sadly a portion of the powder was lost.
-matt
Yes it takes a delicate touch to keep every speck of the powder especially those very fine spherical types...
I alway work to have the bullet just drop free of the casing as in the kinetic puller. When separating the bullet and powder I work over a clean piece of typing paper, as I pour the powder into the scale pan. Small paint brushes can help sweep any loose powder off bullets, fingers or the puller. This is an art form to be very meticulous and not loose any, but I am anal when it comes to the pull-downs!