Question for the blue dot crowd.....

[849ACSO]

I have been tinkering with a 92 action rifle in 357 Mag and cast bullets. I have some blue dot that a friend gave me, and after some reading and research, worked up the following:

-Federal cases-once fired
-Missouri bullet 158 gr "ranger" cast slugs (18 bnh)
-8.7 grains BD
-CCI standard spp
-Crimped at grove (don't recall oal and not where I can get it easily)

This load shoot over my chrony averaged 1575 fps with no signs of pressure, no signs of leading and super accurate (3 touching at 50 yds with factory iron)

Sound right to you guys? Lyman manual (word of mouth from a friend, don't have that one myself) lists start for that slug and powder at 9 grains.......and the 9 grains listed running slower with a mag primer.....

Thinking I will be seeing lead if I go much harder....don't want to scrub....

Thanks,

Matt

 

[Clark]

The no Leading doesn't sound right at bnh 18 and 1575 fps.

I have had disaster at slower velocities, harder bullets, and multiple lube bands, not just one.

I am not going that fast without a gas check.

 

[849ACSO]

I just realized I had the fat finger......it should have been 1475 average. Even though, it still sounds a bit fast for the charge and no lead.

 

[849ACSO]

And I guess I should be be a better poster....

I failed to mention the chrony was at 10 feet, barrel is 16" long and there is a nice lube ring at the muzzle after a few shots.

The numbers just don't add up to me, unless I'm missing something.

 

[FrankenMauser]

Depending on seating depth....
You could be on the edge of Blue Dot's "sweet spot".
It tends to ramp up the pressure as you approach compressed loads. Erratic performance and pressure spikes show up. Then, it suddenly becomes docile as pressure plummets and then slowly comes back up again (with charge weight increases).


...Or you could be beyond the "sweet spot" and right at (maybe over) max for that load. Small pistol primers can withstand up to 35k psi. Some brands will show no 'pressure signs' even at that pressure level.




Personally, I won't touch Blue Dot, outside of magnum shot shell loads (which is what it was designed and intended for).
It's a nasty, evil demon, lurking in the shadows, just waiting for its chance to jump out and cause 'spontaneous' over-pressure.

 

[mikld]

If yer not getting leading, don't worry about it. If your bullets fit your gun and they are carrying good lube, there's no reason a 1500 fps, non-leading load can't be achieved! I've never had any good results trying to figger the BHN vs chamber pressure recipe/theory so I just cast my bullets from WW plus a bit of tin for a BHN of around 12-14, and shoot low-medium Magnum loads in my .44 Puma.

BTW, don't rely on "word of mouth" for load data (my word of mouth is often wrong as sometimes the mouth and brain don't connect with 100% accuracy). Your load is apparently a good load, so now load up 50 and give it some more barrel time..

 

[849ACSO]

The "word of mouth" that I spoke of was me calling him and him reading the load data to me from his manual over the telephony. A little safer than "whaddya think?", but I understand your comment.

Thanks for the replies. Just thought it was a "light" charge compared to the manual's numbers for that bullet speed. I'm pretty satisfied I'm somewhere in a "safe" range for the load. Just wanted to know what others that were more familiar with BD had to say.....

 

[TimSr]

Sounds right. That's like a .38 spl +P load. I was loading 11 or 12gr and getting almost that velocity from a 6" revolver with 158gr SWC with no leading.

 

[bigD01]

blue dot

I've been loading 8.0 gr with a mag primer 155 gr Mastercast lead in my .40 S+W.
Lyman #48 lists 8.0 as a starting load. So far, no signs of pressure, but it does
show lesding of my barrel.

 

[849ACSO]

My understanding of Blue Dot is it likes to be near the "hairy" edge of the max loads in handguns. My load is not near the max, but I worked it up for a rifle with a 16" barrel. I was figuring the longer barrel would give higher velocity and extended time of pressure in the barrel would help seal off the bullet and stop leading with a lower charge. So far, I am right. I don't think I'm going any higher with that load since I have the velocity and accuracy I want without the leading.

 

[44 AMP]

A quick check of some old manuals gives me only one load for Blue Dot in .357 158gr JACKETED bullet. starting load 11gr, max 13gr.

No load found for Blue Dot and cast bullets in my manuals.

1970s era Lyman manual, no load with Blue Dot in .357 Mag, at all....

Good Luck!

 

[chiefr]

^^^^^^
I have a number of old Hercules and other manuals. Some from the 30s thru 60s. There was plenty of published data out there for Blue Dot loads for handguns carts back then.

Sometime in the 90s, Hercules or Alliant determined Blue Dot was unsafe with many of the loads listed. They discontinued all 41 Mag loads and publicly said Blue Dot was unsafe in 41 Mag due to pressure issues. Ironically, I had been loading Blue dot in 41 Mag for 20 years and other carts as well.

Perhaps someone can provide more info on why Hercules quit publishing a number of Blue Dot handgun loads.

After the issues with Blue Dot were revealed, I quit using Blue Dot all together. There are plenty of powders that work just as good or better.

 

[FrankenMauser]

Perhaps someone can provide more info on why Hercules quit publishing a number of Blue Dot handgun loads.

They started using more sensitive test equipment, and saw that there were previously-unseen pressure spikes occurring.

What had appeared to be a safe loads in the past were shown to be dangerous, with better test equipment.

I've done some work with Blue Dot, but I gave up on it. It's too temperamental, too unpredictable, and can be difficult to find a good load with. It was never intended for centerfire use, anyway. It was designed to be a heavy payload shotgun powder (16 to 10 ga) with moderate to heavy compression. It does very well in that situation. ...Not so well anywhere else.

 

[chiefr]

^^^^^^ Thanks Frank

 

[44 AMP]

What had appeared to be a safe loads in the past were shown to be dangerous, with better test equipment.

I'm not saying its not the case in this instance, but I've always wondered about this kind of thing in general.

It seems to be something that has affected the entire firearms & ammunition industry. Pressure readings, and what is /was safe, and now is not...

What I mean is, in the old days, using they methods available, standards were set, and they were safe. Now, with better measuring methods, the "safe" thing from the past is unsafe.

But the safe level from the past was safe. SO why isn't it still safe?

IF, for instance, a load works, gives no measurable safety issues and is in use for years or decades, and we all think it is 35k psi. OK, now we get more accurate measurement, and we find that 35k load is actually higher, say..43k psi (numbers for illustration only)

OH, that's too much! Its not safe!

Why?

Well, because the safe limit is 35k...

But, you thought it was safe when you thought it was 35k, why isn't it safe now?

because it's above the limit!

?

I found Blue Dot to work fine as a moderate load in my .44 AMP. Better than Unique. Never used it in anything else.

 

[chiefr]

^^^^^^^^^^^^^^^
Interesting. As a senior reloader and mentioned in an earlier post, I have a number of old manuals. Between then and now, I have noticed 100s of reductions.

Have heard a myriad of theories as to why. Most commonly, the lawyer theory.

 

[849ACSO]

I've not been at this near as long as most of you guys, but in my 20 year law enforcement career I have noticed a trend that may or may not have a bearing.

I started in 94 and the common handguns were the L frame Smith 5 and 686 guns, some N framed 27's, with a few K's mixed in there. The common auto was the steel framed Smith guns, both wonder nines and some 40's by then.

Now, revolver wise anyway, it's aluminum and scandium and autos are plastic.

I'm thinking the bank vault tough L and N frame .357 guns were just tougher and tamed recoil and absorbed pressures better. Even the K's were found inadequate for a steady diet of the heavy stuff.

That in mind, the ammunition manufactures backed of some to avoid having loads that are ok for my gun but not yours. A lot like we see with the "factory" 45-70 loads.......loading them for all guns in good condition.

 

[Sure Shot Mc Gee]

Using B/D. If there are no excessive pressure signs or leading observed. And if it groups well. Don't change any of your components die measurements or especially your crimp. Not even your bullet lube. Just go on using & enjoying what you discovered. i.e a darn good recipe for your rifle.


357 is what I call a dual purpose cartridge. There is a slight difference in charges between its pistol & rifles use. {Having allot to do with barrel length and chamber pressures developed} And in many instances that is sometimes forgotten. Because you have recipe that is a grain or two below a listed pistols recipe doesn't always mean it won't work in a rifles application. I suspect you found one of B/D sweet spots for your particular rifle at (8.7) Congratulations.

 

[Snyper]

As a senior reloader and mentioned in an earlier post, I have a number of old manuals. Between then and now, I have noticed 100s of reductions.

I suspect those reductions have a direct correlation to the number of lawyers working for the companies

Otherwise, they wouldn't have needed "more sensitive equipment" to find dangerous pressures

There would just have been guns blowing up

 

[WESHOOT2]

there are no lawyers at the loading bench.

Factually, in the past much development was done without benefit of any pressure testing, let alone modern repeatable precise measurements that we get today.
When more modern methods became common old data was found to be suspect, and all too often dangerous.
Hence the changes in data.

Know what I mean?