Powder level

[kestak]

Greetings,

How low is it too low? I always start my reloads to the minimum +.5 grains for my rifles because I am afraid to have a charge that is a few 1/10 under the minimum. If they say 41 grains for a caliber, let's say 308. In a 24 inch barrel, will 35 grains make a squib?

I want to say that I DO NOT WANT TO DO THAT. I AM JUST CURIOUS AND IT IS A PURE RETHORICAL QUESTION.

Thank you

 

[loadedround]

I don't quite understand your question, but if it refers to starting below the minimum load and working up, I would not recommend doing that. Never go below the listed starting load. If you are asking if it's Ok to start at 5% below maximum and working up, I would not recommend doing that either. Follow you reloading manual and work up from the starting load and stay safe.

 

[NotSoFast]

IF you always start at minimum load you won't have problems. Why would you want to go below that and risk damaging your rifle? That will eventually bite you.

 

[Archie]

If one checks different loading manuals, one will find one manual lists starting loads below what the other manual lists as absolutely the minimal load.

Why minimum loads and no going lower?
With certain slow powders, one may encounter either a squib load - the bullet stuck in the bore - or the charge can detonate and blow up the firearm. However, as noted, a minimum load is not always a minimum load.

Usually, manuals use slightly different components. Bullets vary in construction and therefore give different pressure levels with the same powder charge. Cases have different volume and thereby give different pressure levels. Therefore, different minimum and maximum loads.

Probably half a grain from the minimum won't give too much trouble, but at some point, trouble obtains. Sounds like you're doing okay with your proceedure.

If you want to pursue this study further, I suggest the book Firearms Pressure Factors by Lloyd Brownell, PhD. Wolf Press published it when I found a copy.

 

[kestak]

Greetings,

Like I said, I don't want to do that. I am just curious to know if the minimum load is the minimum to avoid squibs.

What makes me think about that it that some people use pistol powder to reload some bolts actions. Especially for subsonic rounds. That means a lot less pressure than using the minimum rifle load. So why don't they use for example 30 grains instead of the minimum 41 grains and they use instead Unique powder.

My question is of pure rhetoric. I am a guy having weird questions in my mind...that you REALLY don't want to know.

Thank you

 

[Archie]

kestak, you pose a good question again about using pistol powder for light loads.

Please understand the pistol powder loads have pretty close to the same MAXIMUM pressures as the full velocity loads. However, the pressure curve is much steeper and therefore less velocity is produced.

Not to mention X grains of Unique is probably cheaper than XX grains of 4350.

 

[243winxb]

What makes me think about that it that some people use pistol powder to reload some bolts actions.

Cast bullet loads for rifles use fast pistol powders. The fast burn rate makes enough pressure to burn the powder correctly. There is no set rule. If you look at H4895 data, then do a search for there Hodgdon "youth loads" you will see you can go below published minimum on some calibers. But only H4895 because there is published data for it.

 

[rcmodel]

Many slower rifle powders simply won't burn consistently at the low pressures you would get by going below the recommended starting load.

Very slow rifle powders in over-bore calibers actually present a safety hazard due to a phenomenon known as SEE, or Secondary Explosion Effect.

Some, including myself, think it is caused by a primer flash-over failing to fully ignite the powder charge. Then the bullet stops moving when it hits the rifling, at which point, the whole charge lights off and pressure builds so fast the stuck bullet can't get out of the way fast enough.

This is not a factor with light charges of fast burning pistol powder in rifle cast bullet loads.
If it lights at all, it all burns.

Plus, grease lubed lead bullets used in those loads are not nearly as likely to stick in the bore as jacketed bullets.

The best thing to do if follow the published starting load data, and use it without further reduction.
It has been tested to be safe & consistent pressure.
Reducing it further has not.

rc

 

[243winxb]

If they say 41 grains for a caliber, will 35 grains make a squib?

This is where you follow loading data. 10% off the maximum will give you a starting load of 36.9 minimum. Any thing under that, depending on the powder could give you a squib load. The slower the burn rate, the larger chance it would happen. Put a match to a pound of powder in the open air, you will get the idea.

 

[qajaq59]

I always start my reloads to the minimum +.5 grains for my rifles because I am afraid to have a charge that is a few 1/10 under the minimum.

No, you don't have to go to that much of an extreme. The manuals do have a little fudge room in them. Although not a whole lot, so try to keep within their boundries.

 

[kestak]

Greetings,

Now I understand. Thank you all for the answers.

I just want to point out I am no longer a new reloader. I load 23 calibers and I have tens of thousands of loaded and shot rounds in many guns behind me now.

I am just a very curious guy who prefer to ask than to try (and blow up my face..hehehehe). I have a friend that we say loads just enough powder for the bullet to fall from the barrel...hehehehe He has more than 40 years of reloading behind him with no accident. And hen we have an acocintance who blew up 4 guns (twice the same). His last one was a 7mm magnum .

Thank you

 

[qajaq59]

And then we have an acocintance who blew up 4 guns (twice the same). His last one was a 7mm magnum .

Ahhh, I suspect that you don't sit next to him at the range much, do you?
LOL

 

[kestak]

Greetings,

When he gets into the shooting area my friends and myself move out.
His last stunt was that he shot a round into the ground behind the line.

About the 7mm Magnum, I still wonder what happened. He said he was fireforming his brass. Even if you fill up the case with the powder you were supposed to load (maximum capacity of 83.2 grains) I doubt he would have blown up the gun. He must have used the wrong powder. No one saw what he did, but we suspect he jammed something in the case instead of doing it the right way....

I am still wondering why he has not been banned yet...:banghead:

Thank you

 

[Ed Gallop]

Your friend is lucky he hasn't maimed or killed someone with 40 years of carelessness. I am not familiar with public range shooting but have heard some frightening stories. All my shooting has been on a police range. Now that I retired to the country I shoot on my own property. Don't know what I'd do if I had to resort to public ranges.

My son joined a private range in Chesapeake, VA and, from what he had to go through to become a member, it may be as safe as police ranges. I was impressed. It would seem to me that there would be more private ranges available.

 

[kestak]

Your friend is lucky he hasn't maimed or killed someone with 40 years of carelessness.

I think I wrote it badly: I meant he is always at the lowest range of the loading data and he is seeking the smallest recoil for the caliber. He NEVER had any accident occurring to him, contrary to the acquaintance.

Thank you

 

[qajaq59]

It always puzzles me why anyone uses some load that they dream up out of the sky. Especially, when they don't even have a clue as to what they are doing. (And yes, there are some that do know, but they also know how to take precautions.) The manuals have a well over a hundred years of info in them that is proven to be safe and effective.

 

[Steve C]

If they say 41 grains for a caliber, let's say 308. In a 24 inch barrel, will 35 grains make a squib?

Manuals list recommended start loads 99% or the time, not minimum loads. Minimum loads are listed for the few rare powders that are density sensitive and require a high load volume to properly ignite, notably H110/W296 in handgun loads. A 10% reduction from the maximum load is generally considered a safe margin to allow for differences in things that affect cartridge pressure like components and its ASSUMED that the loader wants to maximize their velocity for the cartridge listed.

Other than the previously mentioned volume sensitive powders, you couldn't get a squib with a 50% reduction of the maximum charge if you tried let alone using anything near the recommended start load. Most of the time when you see a squib its NO POWDER or contaminated powder.