243 Reloading Escape

Deermanagement

Well-Known Member
Reloaded this last 14 years 22/250, .243 and .30 06 without an issue until now and I thought it a good idea to remind everyone of complacency ...

Managed to get away last weekend, Saturday for Sika and Sunday morning for Fallow and Muntjac. Fired a few rounds middle of the week with my usual .243 load, 95g Ballistic tips, recently loaded, just to check zero. All was well so off to Dorset I went but as with Sika, a couple of clicks adjustment was made for the 100g Partitions used on these animals.

Saturday first thing, shot a pricket and stag calf without issue. After lunch, found the fantastic young 9 pointer I filmed back in October, a stag which came in to about 12 yards and stood to be filmed in bright light for a few minutes before catching some scent. Either side of the laid up stag were 2 prickets, and after a a rather slow stalk in to about 120 yards both I and my camera woman (wife) were in position with a steady rest courtesy of the sticks and right elbow rest against a suitable tree.

All was under control for a neck shot which was taken without hardly a twitch from the pricket. The stag stood at the shot giving us some further decent video footage, however, the follow up reload proved difficult with a jammed bolt. With a bit of force it opened, case ejected, I chambered a second round initially to ensure I was loaded just in case the first pricket showed any sign of life. Without too much thought in the heat of the moment I waited until the second pricket presented a shot, which it did after a minute or so. Once again a neck shot dropped it instantly. A quick reload was again an issue..... jammed bolt!

Once again considerable force to open it but this time checking the case and yes.... pressure.... considerably too much!

With 2 to gralloch and 4 to get back to the larder, stalking finished early. With that sorted and time to consider the issues I though I probably have an issue with the partitions I loaded at the end of last season. The BT's were fine so I was happy to use them next morning and with the few used to check zero and 2 fallow and a muntjac buck clean shot on Sunday morning there was obviously no issue with these.

So tonight I checked out the remaining 8 Partitions I have loaded and yes, 6 loaded heavy and 2 ok. The 2 must have been from a previous batch and the others loaded for a final outing last February in Dorset.

Ok.... loaded heavy, I'm still in one piece but after all those years without and issue, I managed to load up with 48 grains of H4350 instead of 40.8g!

I do not know how much extra pressure this has generated but know it was considerable and consider myself lucky to have both gun and myself in one piece. I know I have not been the first person to make this type of mistake with the RCBS scales as I'm sure many have but being involved with engineering and quality all my working life, if I can make the mistake I'm sure others can and therefore advise ultimate care whilst reloading.

Thankfully the Tikka M590 is well made. During proof testing, loads are used, I understand 25-50% higher than standard loads but I wonder how much extra pressure the 48g of H4350 generated. Next thing would be, has any permanent damage been caused? If anyone can advise I'd appreciate it.

A very fortunate DM
 
Hmmm..... a 20% overload, thats nothing mate i managed to cram 11.6 grains of HS6 into a 38 super case when the load should have been 6.6:eek:
The serations and the scale on the beam of my scales did not quite line up so i inadvertantly dropped it onto +5 grains!!
The first shot in my Springfield 1911 Factory Comp was very loud blew the back of the case off some of which escaped out through the firing pin slot and peppered my face, safety glasses saved my eyes!!
The slide was completely locked up out of battery and took several sharp blows with a copper mallet to close the slide.
The pistol was undamaged mainly due to the ramped barrel which offered much better case support then a standard 1911 barrel.
I was unscathed and i am glad that you walked away from your mishap as well DM, a lesson learnt me thinks

Ian.
 
Glad no serious injuries above.
I use a balance beam and then always check every powder load with a set of electronic scales. It takes a little longer to reload but its time well spent when you think of the potential ramifications.

ATB 243 Stalker.
 
Very pleased to hear that you were not injured. Honest threads like this are valuable, so thank you for posting the experience.
Some time ago I started a thread 'Reloading Howlers - Just for Fun', to which quite a number of our members contributed. It all goes to help others who are new to reloading and to remind those of us who have been doing it for years, that mistakes can and do happen to us all.
Best regards.
 
In all my 15 years of reloading I overcharged some 243 rounds (only once) - I wondered why I was getting a nice big muzzle flash & a big bang! I had done a similar thing - messing up the scale setting.
That is why I now always cross check - I auto dispense powder & weigh the charges on a beam scale system I made & then every few loads I tip a powder load into a digital scale pan just to be sure. It takes very little time & gives me that bit of extra confidence in what I'm doing. Measuring twice on different scales means an error will be picked up almost without fail.

Ian
 
have had my fair share of errors but the overcharge scenario with rifle cases is easily diverted using a powder that offers a high percentage case fill
Those that are slower or have a lower density

I use N160 in .243 and .270 as there is no real way to wedge much more than a sub 10% over charge as the case won't take it

Also using a thrower or scoop and either leaving as is or trickling means the error can ONLY be either:
- a double charge (which wont physically fit in the case
or
- a much smaller variable with a trickler
 
Thankyou for posting that, a lesson for us all, I make certain to do no reloading if I am tired,etc, as mistakes are very easy to mistake when you are distracted.
 
the overcharge scenario with rifle cases is easily diverted using a powder that offers a high percentage case fill

That is one of the reassuring things about loading compressed charges, as you know that there isn't any scope for going wildly over.
 
So tonight I checked out the remaining 8 Partitions I have loaded and yes, 6 loaded heavy and 2 ok. The 2 must have been from a previous batch and the others loaded for a final outing last February in Dorset.
Ok.... loaded heavy, I'm still in one piece but after all those years without and issue, I managed to load up with 48 grains of H4350 instead of 40.8g!
I do not know how much extra pressure this has generated but know it was considerable and consider myself lucky to have both gun and myself in one piece.
[...]
Thankfully the Tikka M590 is well made. During proof testing, loads are used, I understand 25-50% higher than standard loads but I wonder how much extra pressure the 48g of H4350 generated. Next thing would be, has any permanent damage been caused? I
A very fortunate DM

What was you COL? QuickLoad indicates that with a COL of 2.650" you produced, best you sit down for this, 91,200 psi and 3550 fps. The maximim service load for the 243 Win is only 60,000 psi. A proof load would be 30% over that, 78,000 psi. You were well above that. You may have deformed the action - it may have stretched beyond it elastic limits. You should send that rifle to the Proof House for inspection and re-proofing. If they pass it, fine, it they condemn it, be grateful and look upon it as them saving your life. If you continue to use it, you are will be engaging in a dice-tossing game with your life.

You're not the first to do this. A friend of mine put 78 grains of the wrong powder into his rifle, a 338LM, and produced a similar pressure. He couldn't get the bolt open. Later, he discovered what he'd done.

There but for the grace of God ....

-JMS
 
What was you COL? QuickLoad indicates that with a COL of 2.650" you produced, best you sit down for this, 91,200 psi and 3550 fps. The maximim service load for the 243 Win is only 60,000 psi. A proof load would be 30% over that, 78,000 psi. You were well above that. You may have deformed the action - it may have stretched beyond it elastic limits. You should send that rifle to the Proof House for inspection and re-proofing. If they pass it, fine, it they condemn it, be grateful and look upon it as them saving your life. If you continue to use it, you are will be engaging in a dice-tossing game with your life.

You're not the first to do this. A friend of mine put 78 grains of the wrong powder into his rifle, a 338LM, and produced a similar pressure. He couldn't get the bolt open. Later, he discovered what he'd done.

There but for the grace of God ....

-JMS

COL for this load is bullet/chamber is 2.700" giving "ogive to land" clearance of 0.020" although I usually push them a little deeper, to around 0.030" clearance. The overall lengths where initially checked out using the RCBS precision mic and by trial, pushing bullets to different depths to engage the rifling which both confirmed this rifle's chamber sizes. I would have thought that bullet clearance or lack of it would be a more reliable indicator of pressure generated but obviously slight differences in chambers will make big differences.

Does QL have the facility to enter a COL of 2.690"? If so, even higher pressure???

Either way, I'll checked out chamber sizes initially and if anything has moved it should be easy to measure. If any material has passed it's yield point there should be a detectable difference between std chamber sizes and this one. I'll just need to find std chamber sizes. I did do a quick check on case size dimensions and there was maybe a thou difference between these and other cases fired through this chamber previously.

Maybe I should just bite the bullet....not literally..... and give this rifle a birthday with a new barrel. Shame though, cos it still, or did still shoot 0.5 MOA groups with the lighter BT's even after something like 20 years of use.

Did consider the change this year and maybe I should use another rifle for the winter and look for a new rifle/barrel along with the new scope I've been thinking off.

JMS...appreciate the info though....thanks for the advice

DM
 
You cannot always rely on reloading data from one source either. I recently loaded some 416 Rigby with 300gr Barnes bullets using Barnes' data. Should have noted they listed the same charges for H4350 as for IMR 4350. I used the starting load with IMR and recoil was brisk to say the least. Had flattened primers as well as getting cut by the scope after 6 rounds. Got home and rechecked the data then broke down the remaining rounds to confirm I had not made a mistake. Everything checked out per Barnes data but then I noticed they did indicate a charge difference between the two powders for other bullet weights. I also checked some other references and found the same variation in charge weights between Hodgon and IMR for various bullet weights. I figure I may have had a 10%+ overload, the Ruger 77 handled it well though...

SS
 
Does QL have the facility to enter a COL of 2.690"? If so, even higher pressure???

DM

As you seat the bullet in deeper (shorter OAL), the peak pressure increases because there is a smaller volume within the case. Conversely, when you move the bullet away from the lands (or you shoot the ammo in a rifle that has a longer freebore) the pressure drops*. QuickLoad automatically takes this into account.

* This is why rifles based on (relatively weak) shotgun actions have exceptionally long freebores, so that they can fire standard factory ammunition without mishap.

It isn't just the barrel of your rifle that been subject to excessive presure, it's the bolt and receiver of course. Fitting a new barrel won't repair any damage that's been done to the receiver and bolt. If I were you, I would submit the rifle to the Proof House for inspection and re-proofing. The rifle might be prefectly OK, but unless it's inspected and tested, you won't know. Every time you pull that trigger, you'll be wondering if this is the one that's going to let go.

If you won't get it reproofed then scrap it, take a sledgehammer to the action to prevent it being re-used. What value do you put on your eyesight, your fingers? What value do you put on your kids having a father next Christmas? Not being dramatic, but would you drive a car knowing the brakes might fail at any moment? Of course you wouldn't, so why put a questionable rifle next to your head and pull the trigger. Russian Roulette, that's what it is. :)

-JMS
 
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