Getting the holes closer together

[toallmy]

I have been playing with my GP 100 for around a year or so , and have yet to find the ( O that's nice ) load out of it . I have tried a couple different wad cutters out of it as well as the RCBS 150 and saeco 158 gr swc with out getting a tingling felling of satisfaction on target . As of yet all my loads have been very mild probably not even up to 38+p but I think I want to try speeding them up just to see if that helps . I just so happen to have a few pound of w 296 on the shelf that seems to not be going away fast enough in my 410 loads . Now with total honestly I'm not that good of a pistol shooter but I have shot decent shooting guns in the past so I kinda expect better than what I have been able to achieve . My cylinders are true to fit .358 and I have no problem with leading but lacking in on target is a problem .

[country gent]

The old bullseye standard load was 2.6-2.7 grns bullseye and a swaged hollow based wadcutter. At one time this was probably 80% of the ammo on the lines. It shot good in almost every gun. Work from a solid bench and rest when testing. Use a wind flag also. Work with Bullseye,ww231, unique, and HP 38 for the lighter to medium loads. 2400, blue dot, unique, and others in this range for the heavier loads.

[tazman]

I had an issue like yours with a GP100 a couple of years ago. The load I finally found that would work in it was full power 38 special loads under a Lyman 358311. This was the only boolit it shot well.
Since a lot of my ammunition is something else, It went down the road.
My other revolvers all shoot better than that one did with other loads.

[toallmy]

I just came in the house from shooting and best so far has been the RCBS 150 swc over 4.5 red dot in 38 +p brass , and the hbwc are good to as long as I keep at 25 yards off a rest . It's probably like a dog chasing its tail to try to make the ammunition better than the shooter but I am going to keep trying . But no matter what I have tried so far the faster seams to do better . That's what makes me want to step up the power but honestly I wanted this handgun for light cast only loads . Just curious if other gp shooters find faster seams to shoot better .

[gray wolf]

You talk of low power below 38+P, from that to 296 is a big jump in Vel. and power.
Some folks have mentioned the old, and still tried and true 38 Spl. load.
Did I miss what Caliber your loading ?
Is it 38 or 357 ? or 38,s in a 357.

[toallmy]

The revolver is a 357 , I have tried using both 38s and 357s so far the best shooting have been 38s and it is starting to seam like the gun prefers boolits faster than I have been using . So I thought about jumping to the other end and trying out some hotter loads .

[dhom]

How soft/hard are your bullets?

[toallmy]

I generally cast with 50/50 coww and soft lead , but I have tried straight coww I haven't seen any difference on target between the two . It's probably me jumping around with load combinations instead of just shooting and getting the feel of this handgun without going cross eyed tried to fix something that isn't broken . I appreciate you gentlemen taking the time , I think I am going to just try wearing out this revolver by shooting it and it's a sturdy one .

[Eutectic45]

50/50 coww and soft lead is really soft, good for light 38 loads 3 - 3.5 Bulleye or equivalent. Either your RCBS 150 or Saeco 158 gr swc should be fine. I would lightly coat with one of the ALOX coating lubes and shoot them unsized.
Use straight WW or hardened WW for 357 loads for best accuracy.

[dhom]

I would check the bore size. [slug the barrel] My GP100 was finicky but I found some loads it likes eventually. Try the Saeco 158 in a .38 case with 5 gr of Unique. I have found that load to work in multiple 357's.

[JBinMN]

I am curious. Are you using sandbags, or a rest when you are firing? Or, free hand(one handed or two handed)?

The reason I ask, is that when I read these types of topics, I find that not all of the folks say whether they are using some support to test the firearms accuracy, before they start to wonder why the firearm doesn't shoot quite like they would like. Then later , find out that they are shooting freehand & thus it is possibly more than just the firearm, and may involve something in a shooters "form" when shooting.

In the past have had friends tell me that they have a firearm that they can't do well with and I ask them this question about how are they firing & many times I hear that it is they are trying off hand, but have not yet tried in a more stable position like prone or sitting for rifle, or not ever used a bench/tripod/bipod with a rest or sandbags.

Once we put them in a more stable position, or "bench test" the firearm, funny how the weapon does better than they expected and they realize that it is the shooter & not so much the firearm. Once sighted in while in that stable position with the sights/scope adjusted to the intended targets distance, they often do much better. Then it is their "form" that may need work/practice, and they "know" it is not the firearm & is themselves.


No offense intended. Just curious as I did not see where it was mentioned & it does make a difference, IMO. Folks can tell ya all of the things that might help with the firearm, but if the shooters form needs more practice, it would not matter if the firearm was set up & perfectly accurate, there would be "holes farther apart" than was desired. If the firearm is verified to be "off" from the stable position, then the firearm or it's "fodder" might need some work.


G'Luck! I hope ya solve the issue(s).

[44MAG#1]

I can tell you this from watching many people shoot. That at least 80 percent of inaccuracy from offhand or sandbagged benchrest is the shooter.
When one is a member of a club where one has the opportunity to see many shoot, from very good shooters to pitiful shooters, I would say 80 percent is a minimum.
Even benchrest shooting has to have good technique. Bad technique bad accuracy.
Pile on me. Let me have it.

[ShooterAZ]

I would suggest to try a different boolit profile such as the RCBS 38-140CM or 38-158CM. These are "Round Flat" style boolits, and in some (most) of my guns shoot much more accurately than the traditional SWC styles. Worth a try anyway.

[toallmy]

I am by no means a good pistol shooter so shooting off a rest is a must for me when really trying to see what the gun will do / and this makes playing with loads much more trouble . It just seems like this GPS 100 seams to do a little better with everything I have tried at the top of what I have tried , but all I have tried have been pretty mild loads . That's why I am considering jumping to the other end of the spectrum there are perfectly safe loads at the hotter side that I haven't tried and may show me something new or it could teach me how to remove a lot of lead . . I may be back in a weak or so asking how to remove a lot of lead . I appreciate you gentlemen taking the time to offer a hand .

[JBinMN]

I am by no means a good pistol shooter so shooting off a rest is a must for me when really trying to see what the gun will do / and this makes playing with loads much more trouble . It just seems like this GPS 100 seams to do a little better with everything I have tried at the top of what I have tried , but all I have tried have been pretty mild loads . That's why I am considering jumping to the other end of the spectrum there are perfectly safe loads at the hotter side that I haven't tried and may show me something new or it could teach me how to remove a lot of lead . . I may be back in a weak or so asking how to remove a lot of lead . I appreciate you gentlemen taking the time to offer a hand .

Thanks for your reply about whether you were shooting from a stable position or not.

I see/read that you are gonna just keep shooting it & see how the handgun works out for ya.


I also see that there are folks here who are offering good advice to ya, but I would like to try to help a bit more, if I can. Might be a ramble, but I mean well.


I am gonna just offer a suggestion or two, and you think on it & see what ya might want to do... Up to you, but It may help a little bit if you or others haven't thought about such things before.


I am a firm believer in the K.I.S.S. method of doing things. In your case, from what I have read, it might be so simple as removing some of the variables from the situation to get a better idea on what to do.



If I was thinking that I wanted to test a firearm for accuracy, I would want to remove all of the variables that might cause issues. So, I might say, "OK, I am only going to shoot this firearm in a certain stable position, at a certain distance, with certain ammunition.

By doing that, I reduce any issues with any variables to 4 basic things. Most folks would call them, "constants". "Non -variables" held to a standard.

• Type of firearm
  
• Shooter ability with that firearm
  
• Distance to shoot accurately
  
• Ammunition quality & conformity

#1 is the firearm. Is it in good working order & are the sights in good working order? ( + Is the scope in good working order, if a scope is being used?)

[ If you are not able to know if the condition of the firearm & its' sights are in good condition, one cannot expect or be confident that there is not a problem with that firearm.]

#2 is the shooter. Is the shooter able to do the testing with that firearm capable, familiar with its' operation, & do so accurately from a stable position?

[ If the shooter does not have familiarity with the firearm & its' function(s), then there is likely to be a concern that it is not the firearm, but the shooter & their capabilities, which will skew the results of the tests.]

#3 is the distance to target. For conformity reasons, the target should always remain at the same distance from the shooters position.

[ Best to keep the same distance from the target when testing, otherwise the changes made will likely have an effect on the final assessment of the firearms accuracy at other distances not tested. Looking for "constants", things that do not have any effect on the testing.]


#4 is the ammunition. The ammunition has to be a "constant', or the , even slight differences between cartridges will cause the combined effects of firearm, shooter, and distance from target to be non accurate as far as the "concern/mindset" of their consistency, but might just be the ammo being used is not "constant", causing "flyers" & other erroneous hits/ misses that will effect the test results.

[Questioning those other things listed before as faulty, when the blame is non quality ammunition being used & its' chances for not being accurate due to the components not being "matched" can make a difference on what ya see in the results of your test(s).. Even the use of same lot number factory ammo is better than trusting just ones own reloads, if there may be a possibility of performance issues to to "inconsistency"... Sure, everyone tries to do a great job of making their own boolits, but if ya use factory, you have eliminated the possibility of some sort of issue you were not aware of in your won reloading practices. You can always go to your own reloads, but you can also know that good quality factory rounds can be a "constant" also. Keep everything, "Constant", so there are no unknown variables to effect the results.]

I realize my post is long & many will have skipped it.. I don't care. I want to try to help out for those who may not understand...

"Consistency", "maintaining a "constant" & reducing any variables on the testing is a must. The more things that can affect the outcome of the tests, if not kept to a minimum will "skew" the results of the test(s).

Wind can be a variable. Temperature also. Even the mindset of the shooter can be one if they are thinking about supper, the argument they had with a girlfriend/missus, or the boss... creating a situation where they are not focussed on what they are doing.. & the results of the tests may not be accurate as possible due to a lack of "focus"..

I have rambled as I was trying to help, not only "toallmy" the OP, but anyone trying to solve accuracy issues. To some, I am "Preaching to the choir" because ya already know this sort of thing. But, for others who do not know these types of things, perhaps they were never told about such things & now they know just a bit more..


I will shut up now.

G'Luck! once again & if you can keep the "constants" constant, & reduce the "variables', you will likely end up having everything work out to your advantage, and Then.. work on the load/boolit/alloy/etc. changes..

[Forrest r]

Sometimes it's best to start over. Don't know what type of targets you're using, I like to use square targets with iron sights. Typically the square targets will have 2 squares/contrast (black/white). I don't care what the yardage is that they are setup at. I want the front sight of the firearm being tested to be as wide as 1 of the squares.
[IMG][/IMG]

Lining the front sight up with the bottom of 1 of the squares and having the edges of the sight even with the edges of the squares ='s bugholes.

When using scopes I like to aim at dots or small circles.
[IMG][/IMG]

Many moons ago I'd use targets like these for the 100 yd line.
[IMG][/IMG]

Anyway if it was me, I'd start over and print up some square targets and set them up @ +/- the 25ft line. Make sure the square is the same width as your front sight for the distance you're shooting at. Why 25ft? Most loads/firearms should have all holes touching @ 25ft. All holes touching @ 50ft ='s the x-ring on a NRA target.

[toallmy]

A lot of helpful information is being shared , and it is appreciated . I have not been able to put it to use yet because the next week or two will be pretty busy at work , but my off season is the winter and getting this handgun to perform is my project .

[ABJ]

I agree with a previous reply about the alloy being a little on the soft side. The coww with a little tin will handle the higher level loads fine. I have a gp-100 also and in 38 cases it does like the faster side of things. My best load is the Lyman 160 round nose, with the max load of ZIP powder. As far as soft loads goes with your 50/50 alloy, I don't own a 38/357 that won't shoot a soft cast wadcutter with 3.5 grains of Unique or 3.4 grains of HP-38 into 1 ragged hole.
And as another member alluded to, only change ONE thing at a time so as to know what result it had.
Getting there is more fun than having got there.
Tony

[Kawriverrat]

Are you gettig any kind of groups. What I mean is, are the 6 shot groups you've fired ending up in the same area of the target ? Even though they may not be as close as you would like. If not something that has plagued a few GP100's is rear sight slop. Meaning the rear sight does not fit snugly in its machined slot in the rear of the top strap.

If this is the issue there are 2 fixes. Shim the existing sight or buy a new better fitting one such as the Bowen Rough Country of which there is no better made adjustable rear sight for this Gun. It would be good to also pass the gun to a known good shooter to see the results.
When I've arrived at my wits end with a gun after trying different things some where along the way I've had some one else shoot it. I've devoloped some unoticed bad habits a few times that were revealed when someone else shot my gun & load in question. I would suggest you give this a try before going further.... Jeff

[toallmy]

A lot hear for me to work with , I suppose l should stop shooting over the truck engine hood and bring my shooting bench home for this work to start with . Then as suggested cut out all the variables or as many as possible at least . The target to fit the sights could be worked out , this could be useful because the sight is quite blocky . I have considered mounting a scope to do load work - then after I'm satisfied and confident with a load remove it . Well it won't hurt to start over , I need the practice sighting and squeezing on target anyway .