SP101 not shooting to POA

[LUCKYDAWG13]

ok guys need a little help with this I'm looking for a load that will shoot to point of aim In my Ruger sp101
so far I only had luck with 148gr DEWC I have been trying to get some 158gr bullets to work so
far not so good all the loads that I tried still shoot about 3" low so before I look for a different front sight or file it down any suggestions I have tried Bullseye / RedDot / Unique what I'm looking for is a 38 load in 357 brass that shoots to POA

[stubshaft]

If the windgage is all right I would just leave it. You can try the 158 with a lighter charge (should raise your POI) or just hold the front sight high. One of my S&W 36's shoots 5" low & 15 yds and my newest S&W 642 shoots 3" low and 3" left at the same distance. Considering these guns were made for minute of man at spitting distances I won't worry about it.

[Adam Helmer]

If your revolver has fixed sights, all you can do is keep looking until you find a load that shoots to the sights. That is the reason I get adjustable sights whenever possible. Happily, my M1911 shoots to the sights at 25 yards with my favorite handload.

Adam

[LUCKYDAWG13]

I was using 6.5gr of Unique I'll drop it down to 6.gr if that don't do the trick I will just adjust my hold then

[Outpost75]

I would bet dollars to doughnuts that Ruger uses wadcutters to zero them at the factory. At least they did when I went through police armorer's school in 1984.

[LUCKYDAWG13]

I would bet dollars to doughnuts that Ruger uses wadcutters to zero them at the factory. At least they did when I went through police armorer's school in 1984.

Funny you would say that my DEWC shoot to POA 215634

[Outer Rondacker]

My 357 SP101 has it etched on the barrel. 125g bullets.

[LUCKYDAWG13]

My 357 SP101 has it etched on the barrel. 125g bullets.

So a 125gr bullet will shoot higher

[Outer Rondacker]

No. I was just making a statement. Mine has the correct windgage but shoots low as well with 38 speeds. I move it up to a hot 158 bullet and its right on. Kicks like a mule for a small gun.

[NSB]

Put a tritium night sight on the gun and get the smaller dot size (sits lower). Between that and using a heavier bullet (not a lighter one) you'll get it pretty close to POA. I played with mine a while before I got it right. Ten shots double action at 25 yards 3.8".

215643

[Outpost75]

So a 125gr bullet will shoot higher

No... A revolver is pendulum in motion so lighter bullets with less recoil impulse and higher velocity will shoot low. Heavier bullets with greater recoil impulse and longer bore time shoot high.

Back in the day (1980s) fixed sight revolvers produced for government contract orders were zeroed using the specified ammunition provided as government furnished material. With the US Customs and Border Patrol, French Gendarmarie and India police I am familiar with the exact specs varied in accordance with the contract specifics. A .38 Special or .357 revolver such as produced for USBP would commonly be shot off sandbags at 20 yards, aiming at a 2-inch bull, or the aiming point being scaled to one inch per ten yards.

A 3" circle was printed on the target rolls, surrounding the aiming point with the circle tangent to the aiming point at 6:00. Five out of six rounds were usually required in most contracts to strike within the 3" circle. The correct front sight height would be determined by firing a ten-board sample of revolvers with the contract ammunition to obtain the correct elevation and then all guns being assembled would be fitted with the same height front sight for that ammo. Windage adjustments would be made in the range when necessary by rotating the barrel in the frame using directed strikes with a babbit bar.

With revolvers point of impact for elevation is determined more by bullet weight than velocity. Bullets of the same weight and type will shoot close to the same point of impact in either standard or +P loads. Getting .357s to shoot to point of aim is different, due to greater recoil impulse, but generalities of bullet weight influence hold true. In ordinary production intended for civilian retail sales it was common to use .38 Special 148-grain wadcutter ammunition for both .38 Specials and .357s because zeroing with this ammo provided a point of impact which was useful for most commonly used ammunition. The lead wadcutter bullet also provides a better functional test to detect "spitters" in which a new fit-up might over-rotate the cylinder (OK up to about 5 degrees to compensate for service wear).

To determine how much to adjustment is needed to rezero fixed sights use the formula X=RE/D where X is the amount of correction needed.

Reducing height of the front sight to moves the impact up.
Installing a higher front sight lowers point of impact.
Rotating the barrel tighter in the frame moves the front sight left to move impact to the right, etc.
Barrel threads are timed and the fit-up checked with a gage so that barrels can be hand-tightened within 7-1/2 degrees of top-dead-center so avoid collapsing the root of the thread and causing "thread choke" from over-torqueing. The barrel thread spec was UNF-2A.

R is the sight radius in inches.
E is the error correction needed between point of aim and point of impact, and
D is the target distance.
ALL dimensions are in inches.

In extreme cases a used old cop gun may have a bent frame from being used as an impact weapon, and/or the crane is bent out of alignment. A competent gunsmith can fix these. There is absolutely no reason why a 2-inch .38 snubby cannot be zeroed precisely and shoot accurately. My own S&W Model 36 former basket case reworked by Sandy Garrett of NoVa Gun Works now shoots ten-ring, 25-yard groups with wadcutters, and quality defense or service loads should do likewise in a mechanically correct gun.

215648

215649215650

[9.3X62AL]

This post ^^^ needs to be "stickied". Thank you, Outpost 75.

[LUCKYDAWG13]

yes thank you Outpost 75
And NSB what front sight did you get
and thanks to all

[shooting on a shoestring]

I have a 2.25” barreled SP101 in .357. It shoots low with 158 gr boolits. I went to the NOE mould 360180 a wide flat nosed boolit at 180 grains and pushed the velocity to 1300 fps. That shoots to point of aim. It’s pretty wicked on both ends of the gun with that load.

Often I run a 160 grain double ended wadcutter in it at about 1100 fps. It goes a little low, but for a defensive gun that might be a good thing as most misses in gun fights tend to be high misses.

My 4.2” SP101 in .327 shoots to the sights with 105 grain to 115 grain boolits.

[FergusonTO35]

I had a 3" SP for awhile. It shot low with everything I tried. Fortunately the front blade is soft aluminum and replaceable, so I just filed it down until it shot like I wanted. That particular SP had a dreadful trigger pull, I ended up getting my money back out of it as a trade-in on a LNIB Marlin 1895.

How do the late model SP's tend to do? The Ruger forum has a real love-hate relationship with them.

[NSB]

I had a 3" SP for awhile. It shot low with everything I tried. Fortunately the front blade is soft aluminum and replaceable, so I just filed it down until it shot like I wanted. That particular SP had a dreadful trigger pull, I ended up getting my money back out of it as a trade-in on a LNIB Marlin 1895.

How do the late model SP's tend to do? The Ruger forum has a real love-hate relationship with them.

Put a Wolf spring kit in the gun and fix the trigger. Even Bubba can do it right it's that easy. Cheap too.

[Petrol & Powder]

My 357 SP101 has it etched on the barrel. 125g bullets.

That is likely one of the early "Short Frame" .357 mag SP101's. When the SP101 was introduced it was chambered in 38 Special. Ruger made some early SP101's chambered in .357 magnum and marked the barrels ".357 Magnum 125-grain ammo only"". Shortly after that, Ruger lengthened the frame and cylinder of the SP101 to accommodate any factory spec .357 mag cartridges. Ruger only made about 3000 of the short frame .357 mag models so they are a bit rare these days.

[LUCKYDAWG13]

Put a Wolf spring kit in the gun and fix the trigger. Even Bubba can do it right it's that easy. Cheap too.

I did that too and yes easy to do and helped a lot

[Outer Rondacker]

I had a wolf spring in mine until I had to send it back to ruger for a timing issue. They took it out and put a 10 pounder back in. :{ I guess I should order another one now that you have reminded me. :}

[Livin_cincy]

Try putting the top of the front blade in the center of the Bullseye.
Put the 'shoulders' of the rear sight down at 6:00.

Find the distance that this sight picture and your load impacts the Bullseye / Black of your target.
This would be your 'Max' range.

Bring your target in until the 'normal' sight picture hits so POA = POI.

Now hitting between these two distances and figuring out the sight picture is practice.
Try painting your front sight in two colours so you have a center line to use as reference.

Good luck.

[FergusonTO35]

That SP went down the road in 2004, however if I ever get another one I will for sure do that. I have a strange desire for a .38 Special model with 2.2" barrel.

[Kraschenbirn]

At 10 yards, my fixed-sight 3" SP101 shoots PC'd 160 gr. RNFPs over 5.5 gr. Unique (.38 Spl brass) to, essentially, the same POA as the 125 gr. JHP +P factory loads I carry for 'everyday'.

Bill

[FergusonTO35]

Interesting, my Service Six shoots about the same with 125-162 grain boolits. If there is a difference my shaky hands can't find it. My S&W 10-5 now, is laser accurate with 158's and low with everything else.

[LUCKYDAWG13]

Thank you all for your tips on this I'm gonna run a few more loads through it in the next week or so
I may just end up having to hold over for these light loads

[FergusonTO35]

You may want to try the Lee 358-150-SWC. It is discontinued but easy enough to find used. It shoots the same as wadcutters in my revolvers. That being said, I think wadcutters may be the optimum choice for a snub nose. They use alot less powder to reach the same velocity.

[Drm50]

I had a SP in 22lr a few yrs back. It had adj rear. It would print with anything it shot low. I got
rid of it. Did alright on windage,

[LUCKYDAWG13]

You may want to try the Lee 358-150-SWC. It is discontinued but easy enough to find used. It shoots the same as wadcutters in my revolvers. That being said, I think wadcutters may be the optimum choice for a snub nose. They use alot less powder to reach the same velocity.

yes after i use up the the 158gr plated bullets I plan on just shooting the DEWC and thanks for reminding me
I think i still have a 358477 mold around I can give them a try too

[Texas by God]

I grew up using a 6 o'clock hold for handguns. One that prints low drives me nuts. My S&W Shield .40 S&W shot low with 180gr so down the road it went.

Sent from my SAMSUNG-SM-G930A using Tapatalk