Groups opening up as 120K power factor is approached (38 spl)

I have a S&W K frame with 6" stainless Douglas 1-10 barrel (red dot scope). With factory Remington 158 gr Target RN (meets 120k power factor) or 148 HBWC 1-1/2" (50 yard) groups are the norm.

With my reloads need to reach the 120K power factor, 148 HBWC shoot great under 800 FPS but are not safe over that...so they are ruled out.

Both 148 BNWC (.358 swaged) and 158 RN (.358 swaged) bullets have great accuracy (under 800 fps) until I start increasing the W231 charge then groups approach 4".

Just for the heck of it I loaded a few Hornady JHP XTP 125 and they spread out at 50 also, then loaded Remington factory 148 HBWC again and back to 1-1/2" groups.

As you all know...it's impossible to get any bullet samples or primers right now.

I know the gun shoots great with Remington factory loads...looking for ideas that I can try like OAL, powder, roll crimp, taper crimp etc to tighten my reloads.

Are you reloading for an Action pistol game or for Precision Pistol? There is no power factor requirement in Precision Pistol.

It seems to be the swaged part. 

I use powder coated BNWC and I can load them to +P with good accuracy.  I do the same with cast H&G #50 I cast my self to about 12 BHN.

Just my guess.  I had difficulties with Hornady swaged bullets at anything but light velocities.  

I don't understand the Hornady JHP thing, they should shoot great.
Brazos is not too far behind on delivery for powder coated bullets.  Their 158 RN shoots great out of my stock Smith and Wesson 38 right up to +P velocities.  It is their BNWC I am  using now.  I get a little better accuracy out of the RN.

David
David

Swaged bullets are NOT for high velocity loads.

Upper40 wrote:As you all know...it's impossible to get any bullet samples or primers right now.

I agree that primers are impossible, but I have recently bought bullets from several vendors - including Brazos. Sometimes one needs to be a little patient to let them catch up on production, but bullets of most types are still available (exceptions - Hornady XTP60's and even 85's, Nosler JHP185's).

Take a look at T&B in Oregon (https://tbbullets.com) for coated lead bullets - very fast turnaround and decent quality. Travis will even size them to your preference.

EvergladesAmmo.com for JHP 45 & 9mm.

Aren't the Remington 158 RN swaged?..They easily make the power factor. Hear negative stories about copper coated bullets...ordered some cast bullets to try about a month ago from GT Bullets....looks like another month wait.  Wouldn't mind trying some plated wadcutters...but can't locate a source that has them in stock today.

FYI Graf and Sons still have some bullets. Three minutes ago they had .32 Lapua. 313, 9mm in several weights, 40 cal spendy, 38 in 158 gr both SWCHP and RN both swagged, 45 in 185gr JHP and some cast.

Another FYI. The 1:10 barrel twist is why you are opening up when you try to push them.

First, I would abandon trying to get any jacketed bullet to meet your 120K PF in a K frame S&W. You will crack the barrel at 6 oclock in the forcing cone. I have seen dozens of these, it will happen. If you want to use jacketed bullets go to an L frame.

There are many who use 148 gr WC in K frame .38 spl and shoot NRA AP meeting that 120K PF floor. You need about 811 fps. Most load to about 830-850 fps. The PF floor in AP is absolute, load above it, so not get get DQed for not making PF. The classic load is 3.5 gr W231 or about 3.2 gr WST or equivalent substitute. I have run cast 148 DEWC as fast as 880 fps with good results. 

Bayou Bullets make an excellent 138 gr BNWC (it is not DE, but not hollow either) hitek coated bullet. These loaded to the upper 800's are outstanding. I loaded 3.9 gr WST. Bayou also has an excellent 120 gr TC hitek coated bullet. I loaded those with 4.5 gr WST to get to about 1020 fps.

Brazos makes an excellent 125 gr RN hitek coated bullet. 4.5 gr WST is a charmer there running about 1000 fps.

Seat the WCs with all of driving band in the case. Taper or roll crimp doesn't seem to matter, provided that you find the sweat spot for each.

For the other bullets mentioned above seat them deep with very little of the driving band exposed, with a firm crimp.

My custom revos are all either 1:14 or 1:16 twist. Yours at 1:10 may be the problem. Maybe try a powder a little slower burning than W231 will help. I think the shorter bullets, 120 gr may help you there, even though, typically, faster twist like heavier bullets.

Last, check that barrel carefully at 6 oclock on the forcing cone. It may already be cracked. The groups open up when that occurs. IT WILL HAPPEN with jacketed bullets at 120K PF loads which are plus P plus using fast burning powders, like W231.

In bullseye slower equals a tighter group so bumping the load to 120 should increase the groups

Just installed the barrel less than 400 rounds ago...so forcing cone is good to go, I'm knowledgeable related to forcing cone damage. I simply shot a few JHP to see if the group would tighten.  With the factory Remington 158 Target 158 RN rounds groups approach sub 1-1/2" (50 yds). Same with factory Remington 148 HBWC.  The swaged bullets I have shoot really great in the 750 range...powder up, groups spread...but no leading.

Just ordered some coated Bayou 160 and 145 RN bullets to try...maybe by Spring I'll have them:-)  Feel that the 1-10 barrel prefers bullets with mass and surface contact area. 

I'll experiment with seating depths, brass variations and crimps..while I wait for bullets.


Thanks

We always pursue the best accuracy. However, in NRA AP you also have to meet the PF requirement. Unless, you are either using a scope with lead, or a mover base, or a Warren Moore lead front sight, then I would suggest that you try to work a decent load with a 120 - 125 gr bullet at 980 - 1020 fps. If you shoot a bullet any slower, then on the mover at 25 yds, you are holding in air! Mathematical lead on the target at 25 yds for a bullet at 1,000 fps is 9". The target AP-1 is 18" wide, thus 9" from center to edge. At 25 yds with a +/- 1,000 fps round, hold lead at edge of target. Just a thought. 

Another thought is the 10 ring is 8" diameter and the X ring is 4" diameter. Of the 192 shots only 12 are at 35 yds and only 12 are at 50 yds. All other 168 shots are 25 yds or less. I gun that that shoots 4" at 50 yds is more than adequate, especially if you shoot it well with that load. 

NRA AP is great shooting game. 

Best wishes, 

Martin J.

Thanks...I designed my own mover base that works great...so bullet speed is only a concern to meet the power factor of 120K.  Been to the Bianchi about 24 years ago with a Manurhin 9mm revolver that shot 1" groups at the 50. Last time there shot a 480X47 barricade which was a record at that time..seems like 480X48 is more common now. I can always fall back on factory Remington 158 for the actual match since I have about 3500 rds of it on hand.  I'm confident that if I can locate some 158 RN bullets with a more "pointed shape" I'll be good to go.

Upper40 wrote:Thanks...I designed my own mover base that works great...so bullet speed is only a concern to meet the power factor of 120K.  Been to the Bianchi about 24 years ago with a Manurhin 9mm revolver that shot 1" groups at the 50. Last time there shot a 480X47 barricade which was a record at that time..seems like 480X48 is more common now. I can always fall back on factory Remington 158 for the actual match since I have about 3500 rds of it on hand.  I'm confident that if I can locate some 158 RN bullets with a more "pointed shape" I'll be good to go.

Zero 158 gr LSWC or LSWCHP are hard to beat at around 775 fps. In the range of 2.5 - 2.6 gr Clays or equivalent, may be worth looking at.

Pulled a couple of factory Remington bullets, both have the cup base, both are 158 gr...but the RN (target) clearly outperfoms the SWC at 50 yards.  




Oh Man!
You shoulda asked!!!!

Bulletworks in TX shows a 158 gr RN (cast) that may be suitable.

https://www.bulletworks.com/bulletworks/USPSA_IDPA.html

DA/SA wrote:Bulletworks in TX shows a 158 gr RN (cast) that may be suitable.

https://www.bulletworks.com/bulletworks/USPSA_IDPA.html

Thanks for the info.,..

The Graf and Sons bullet I mentioned above is a Magtech. Identical to the Remington you are trying to match.

LenV wrote:The Graf and Sons bullet I mentioned above is a Magtech. Identical to the Remington you are trying to match.

Thanks..just ordered some bullets 160 and 158 RN from Graf & Sons...what a lengthy procedure to order from them.  Minimum ($) order and the usual give your credit card info before you have a total etc.  

For some reason "my bullet photos" no longer appear in my posts.

LenV wrote:The Graf and Sons bullet I mentioned above is a Magtech. Identical to the Remington you are trying to match.

You were correct...the bullets are almost identical. The good news is they shoot GREAT!  The bad news in that MEGTECH is getting out of the reloading line and going 100% into ammo production...no more bullets for reloading.  Back to the drawing boards!