problems with bullseye powder

[ckfarris]

So I have about a pound of bullseye powder that I am trying to use up before before I crack the seal on my 8# jug of solo 1000 and thought I would use it on the 1000 rainier plated 180gr rn bullets I had laying around. I am shooting a 5" sti and am having some problems. Here is what I am doing on my Dillon 550:

1.18" OAL

5.2 gr Bullseye powder

Winchester primers

I went and chrono'd this load and out of my 10 shots got a range of 887-1005 fps. This seemed like a huge variation to me so I went back and loaded 10 more, this time double checking my powder charge and each charge was no more than .05 from 5.2. Went back out to the range and same thing.

Anybody got any ideas? Am I loading too long? I like loading to that length because I have always heard that STIs like em a little long and have never had any issues with the length.

[Ed Robinson]

Sounds more like an inconsistent crimp to me. Bullseye is usually very consistent. Check your crimp and make sure it is good and consistent. Crimp is dependant on brass length so if you are using various headstamps that have multiple firings, crimp will be inconsistent at best due to various brass lengths. Find you 20 pieces of brass that are all same brand. Measure length and make sure all are within a thousandth or two at the most. Load with the same powder charge and same bullet. Seat and crimp in seperate operations. If you are seating and crimping in the same die, back off the die body until no crimp is applied, deepen your seating stem to correct the depth and seat all 20. Back off the seating stem, tighten the die body back down until you get the desired crimp and crimp all 20. Run them back thru the chrony and see what happens. Ed

[ckfarris]

I currently seat with a lee die and my 4th stage is a hornady taper crimp die

[ckfarris]

Let me ask this then since I apparently stumped everybody with my first question. If I reduce the OAL closer to the factory recommended (1.125), is it possible that will stabilize my fps? Is it possible that having that much space in the round where I was at was causing the large variations?

[mlmiller1]

Is this a "light" load? If so, that could be the cause of your problems. Some powders loaded down don't react well. If your load data will allow it, try a little hotter load. I suspect your variations will go away. Obviously, don't go over max loads or anything like that but if you can bump that up some & stay in published data, you may find some consistency.

I echo the poster who said variations in brands of brass can cause huge swings in velocity. The neck tension will or can vary dramatically. For chrono work or high accuracy shooting, brand match your brass.

Last but not least(maybe this should be first), check the diameter of your bullets. If they vary much, all other bets are off. You will never get consistent speeds with different diameter bullets.

MLM

[mlmiller1]

Oh yeah, in answer to your most recent question, shorter load length will increase pressure, which may stabilize your velocity. That can achieve the same thing as loading hotter.

MLM

[ckfarris]

Roger that. Thank you ML

[g56]

Use caution when shortening the OAL, pressures can skyrocket with only a slight reduction in OAL. I would try a little more crimp first, crimping can often cause problems with excessive variation in velocities.

Since you didn't mention caliber, which is kind of important, I'm guessing you are talking about 40 S&W. According to Alliant, you are within 10% of the max charge for jacketed bullets, plated bullets should be loaded down a bit more, at the same time you are loading a bit longer than the minimum OAL, so that's probably helping you.

Alliant Powder 40 S&W info

[mlmiller1]

Ok, so you are too hot already, don't shorten your loads. That can cause a dangerous overpressure, aka BOOM! Plated bullets should be loaded lighter than jacketed. I suspect your problem is more in the brass or inconsistent size bullets. Too much crimp on plated bullets will give you problems also. Shredding plating, tumbling, etc.

One other thought just struck me, how far away do you setup your chrono? If it is too close, you will also get inconsistent numbers.

I've gotten away from plated bullets pretty much. Too many considerations for my tastes. That is just me, though. In the past I loaded tens of thousands in 9mm & did ok but in 40 I have never had much luck.

MLM

[ckfarris]

I shoot through the chrono at about 5-8 feet. I am fairly sure that the rainier plating is fairly less consistent that other, higher priced brands. I may just say screw it all and load these up light and then use my BBI's with Solo 1000 at the matches. Thanks to everybody who replied, I am still trying to figure out burn rates, pressures, and all that other fun stuff that comes along with reloading.

[dogtired]

I am shooting right around 4 grains of Bullseye with a lead bullet and it makes major at 950. I think you are too hot with that load.

[BBBB]

The plating on those bullets is thin compared to a jacketed bullet. It is more susceptible to damage during seating and/or crimping and the bullets do not work well when the plating is damaged. I would suggested pulling the bullets in some loaded rounds (or loaded dummy rounds if you prefer) and verifying that plating is fully intact and undamaged. They can be damaged during seating if the case mouth is not belled enough or during crimping if you apply too much crimp.

[Amerflyer48]

as far a slight loading Bullseye is concerned you can load 2.7 grains in a .38SPL casing with a 148 HBWC and it is very consistent and accurate. just ask anyone who owns a S&W M-52

So I would think it is a brass/crimp problem but I don't load .40 much and when I do I use WW231 just to go bang at the range,..I make MAJOR with my 10mm and 38 Super. less KaBoomy maybe some day I will take up the challenge of loading the .40 for competition..

I did mistakenly shoot too close to a chrono once and it gave me some funky readings moved chrono further out (downrange) and it settled down not sure if better lighting or less muzzle blast was the culprit.

"I am still trying to figure out burn rates, pressures, and all that other fun stuff that comes along with reloading. "

Burn rates : they have charts for the relative burn rates..

Pressures: not without proper test equipment,.primer reading is unreliable in my estimation..yep flat primers are HOT ammo but how hot ?? and pressure is NOT linear ..

All the other fun : welcome to your new addiction...

John

[TonyT]

So I have about a pound of bullseye powder that I am trying to use up before before I crack the seal on my 8# jug of solo 1000 and thought I would use it on the 1000 rainier plated 180gr rn bullets I had laying around. I am shooting a 5" sti and am having some problems. Here is what I am doing on my Dillon 550:

1.18" OAL

5.2 gr Bullseye powder

Winchester primers

I went and chrono'd this load and out of my 10 shots got a range of 887-1005 fps. This seemed like a huge variation to me so I went back and loaded 10 more, this time double checking my powder charge and each charge was no more than .05 from 5.2. Went back out to the range and same thing.

Anybody got any ideas? Am I loading too long? I like loading to that length because I have always heard that STIs like em a little long and have never had any issues with the length.

I assume you are loading 45 ACP. I have dound that using the same weight bullet and powder the plated bullets will always provide significantly lower velocity. Secondly as a previous responder mentioned plated bullets can be damaged by overcrimping. I only remove the flare from the belling operation.

Thirdly is you are using a Lee FCD discard and use a normal crimp die - the Lwee FCD tends to swage the bullet in the loaded round.

If that doe not help then I am out of suggestions. Kowever i have used Bullseye for ca 50 years and it always has provided excellent accuracy and very low velocity variations.

PS: Make sure you are ca 10 ft away from the chrono.