Why Guns Blow Up

 Since the inception of guns in the 14’th century guns have been exploding. In the early days it was the metal technology that was at fault.  They were made from brass or wrought iron and just wouldn’t stand up to shooting even with the weaker black powders of the period. The powder of that period were weaker not having much saltpeter and was finer then it is now. Granulations weren’t used then. If fact they were so dangerous that prisoners were used to fire the cannons and if they survived were given a pardon according to an article I read some time back. Of course when iron and later steel use was perfected that pretty much solved that problem. Better welding also helped. Better loading techniques without a doubt helped. 

 Naturally black powder guns can still be blown up with some effort by the user. If you used a ridiculous amount of powder with a bullet that may have been forced in the barrel or oversize that will cause a gun to burst. Another thing is if you seat a bullet an inch or so from the powder that will also cause an explosion. I have an example where a guy used one of those plastic wads in a 45 caliber with 70 grains of ffg of black powder. The wad allowed the bullet to move forward causing the explosion. There is a crack along the barrel for about 18” and the forend was blown off in pieces. The shooter required some medical attention to get some wood and metal particles out of his arm. (See photo) It’s important to make sure that the bullet is firmly seated against the powder. Years ago I bought a used muzzle loading rifle in 45 caliber. I put a regular load in it and upon firing I felt a stinging on my forehead and had some blood coming out. I was sprayed with some hot gas and the hammer had recocked. Upon examination I found that the nipple was for a pistol and had too large of an opening allowing excess powder gas to come out the opening. The correct nipple solved the problem. I wasn’t seriously hurt but was more cautious on buying used guns. Also never use smokeless powder in a black powder weapon. Smokeless generates much more pressure then the gun was designed for. Also if you have an old shotgun with Damascus barrels if you insist on shooting it have it thoroughly checked out first by a competent gunsmith. The same goes with by any other older firearm. It should go without saying that smokeless powder should never be used in such a weapon.

 In the early years of smokeless powder people didn’t understand the proprieties of it and loaded the same as they would black powder. In other words fill the case and seat the bullet. Of course that would destroy most guns in short order. Once the word got out that problem pretty well went away. Another problem was that primers had fulminate of mercury. When fired the mercury would attack the case weakening it over a period of time. If it was reloaded it could cause a case to shatter possibly destroying the gun. In fact it the cases sat around for awhile before loading they could shatter in the die. In the scheme of things that would be better then shattering in a rifle.  Black powder loads covered up the problem because they had lower pressure and the cases were washed between loadings on some occasions. Some older 38 and 357 Magnum cases had large pistol primers which are still occasionally encountered. It you load a max load in those cases the powder may over ignite causing a serious problem.  Starline makes cases for blanks with oversize flash holes for the 45 Colt and the 5 in 1. It allows more flame to go through the flash hole properly igniting the black powder. As long as black powder is used there is no problem however a heavy load of smokeless powder is used a destroyed gun can result. They are marked as blanks on the case head so pay attention when loading your brass.

 One of the early problems was in heat treating the receivers. One outstanding example was the older model Springfields. They were improperly heat treated causing them be have brittle receivers. Ser #’s 800,000 and below from the Springfield Armory and ser# 258,805 from the Rock Island Armory were involved. If you encounter one it’s best not to shoot it. They are still around waiting to cause a problem. I encountered one about two years ago that someone showed me. An amateur gunsmith drilled the receiver for a scope mount and it cracked. They proceeded with the operation anyway ignoring the danger signs. Why they didn’t blow their head off is a mystery. Perhaps God does look out for fools.  Serious injury is a real possibility with shooting such a gun. Improperly heat treated receivers will frequently come off in pieces with quite a bit of velocity. They tend to shatter like glass.  For a real good detailed activity of such explosions see Hatchers Notebook for more detailed info. Many years ago the military use to put a tin coating on their bullets to reduce fowling and increase accuracy. While that worked it was found that the bullet cold soldered to the case neck increasing the power it took to get the bullet out. That along with the grease they used caused some blown up guns and both practices were discontinued around 1920 or so. I have found some military bullets extremely difficult to pull but in most cases if they were seated a bit deeper, breaking the seal, that would solve the problem. I believe that if they were fired the pressure would be higher then normal. I strongly recommend against gluing a bullet in the case under any circumstances.

 Another cause of blowups is firing a gun with the wrong cartridge. A good example is shooting the 8 X 57 in the 30-06. The 8 X 57 is short enough to chamber but upon firing you are doing two bad things. First shooting an 8 mm bullet down a 30 caliber barrel and since the case is shorter the head won’t be properly supported. If it doesn’t actually blow up the gun it will destroy the magazine and stock because the gases have to go somewhere. If you fire a 30-30 in a 303 Savage the results can also be disastrous. The 30-30 case is .02 smaller at the critical head area allowing it to rupture spraying gas all over. There are other possibilities such as firing a 358 Winchester in a 270 or 30-06. That’s why it’s important to make sure that you make sure that you are firing the proper ammo. If you make 7.7 Japs out of 30-06 cases make sure that they aren’t fired in a 30-06 or 270. In fact any time if you form cases from others make sure they are properly separated and labeled. The old 8 mm fired a .318 diameter bullet until about 1904. Shooting the newer .323 diameter bullet can be dangerous especially in the Commission rifle. Factory 8 mm ammo made in the U.S. is pretty weak and is probably safe to shoot in the older guns but I don’t recommend it. As well as being dangerous it probably isn’t very accurate. The 318 and other proper diameter bullets are available try www.obsoleteammo.com. Shooting a 3” shell in a 2 & ¾ “chamber can occasionally blow up a gun. The shot and wad can be constricted for an instant causing an incident. At the very least it will kick harder then normal giving you a clue that something is afoot. I have a 20 gauge double barrel that that happened to. (See photo) Shotguns have thinner steel and are more subject to blowups then thicker barreled rifles. Also cheaper gun barrels aren’t heat treated as well as the better ones. Another possibility is shooting a 357 magnum cartridge in a 38 special revolver. Most of the time the 357 won’t chamber in a 38 but don’t count on it especially in a cheap gun. The 357 is loaded to much higher pressure then a typical 38 which can wreck a revolver. Winchester came out with the 375 Winchester round some years ago. While a good woods round it will chamber in the older 38-55 rifles. Some of them are designed for black powder which making shooting the newer round a dangerous proposition. With such a litigious society, I am baffled, by such thinking by the arms companies.  If you form cases sometimes its necessary to neck them down from a large to small caliber. The neck will thicken during this procedure causing a constriction. Sometimes I make 219 Zipper cases from 30-30’s. I first neck them down in a 25-35 die which is necessary. I then inside ream the necks and trim to proper length then size in the 219 die. If I didn’t ream the necks a noticeable bulge would appear in the loaded 219. Not only would they be very difficult to chamber but they would be hazardous to shoot due to the excessively thick necks. When fired the bullet will get stuck for a mil second causing the gun to blow up. To prevent that either ream out the neck or outside turn it allowing the bullet to exit in a normal way. I can remember years back the American Rifleman had a article about a 243 doing exactly that. They determined that excess neck thickness caused the rifle to blow up. 

  Various barrel obstructions can blow up a barrel though seldom ruins an action. If you have a shotgun and a wad gets stuck in the barrel firing it can cause a serious injury. Since the barrel is thin the shot and powder residue will frequently come out the sides. Since your arm is in the area it will catch the shrapnel. If you fall while hunting make sure there is no mud or snow left in the barrel. I have a barrel that a fellow had and while he was duck hunting he tripped and fell. About 4” of the barrel went into the water and the gun went off. He now has a slug barrel with no choke. (See photo) I have seen a slug shot down a real tight choke blow out the choke giving it wings. A rifle or revolver barrel will generally bulge if you attempt to shoot out an obstruction. I did see one revolver blow out a piece of the cylinder where the notches are when it was fired with a bullet in the barrel. The barrel had a noticeable bulge in it about half way down. Sometimes a 20 gauge shell can be accidentally be put in a 12 gauge. It will drop about 3 to 4” down the barrel. If a 12 gauge is fired in it the barrel will blow off usually causing serious injury to the shooter and bystanders. A 16 gauge in a 10 gauge can cause the same problem. Just make sure that you segregate your shells if you have such guns.    

 In some cases blanks can blow up a gun. What happens is the wadding that some use can get stuck in the barrel around the blank adapter causing an obstruction. Since blank powder is hotter then conventional powder a blow up is very possible if not cleaned out. Also don’t even think of using blank powder for loading conventional ammo. That is a sure recipe for disaster. Blank powder is much hotter then conventional powder.

 I have heard of people pulling 22 rim fire magnum ammo to put more powder in them. Those folks must want to win a Darwin Award. First of all pulling rim fire ammo can cause it to go off especially with an inertia bullet puller. Putting extra powder in any 22 rimfire is asking for a trip to the hospital. The rims are thin and extra powder can blow out the action causing an injury. Since the priming compound is in the rim and the pullet is holding the round by the rim banging it is a recipe for disaster. Never pull any rimfire ammo especially with an inertia bullet puller.  

 Using the wrong powder for loading has blown up more then a few guns. You should always leave powders in the original containers. If you accidentally put a pistol powder in a rifle cartridge it will definitely damage a rifle. I know a fellow that put WW 231 powder in a 222 Remington. Upon firing the receiver, magazine and stock were completely destroyed. It was his lucky day that he wasn’t seriously injured though badly shaken up. He simply wasn’t paying attention and grabbed the wrong can thus destroying a nice weapon.  Too much powder can also destroy a gun though it’s mostly handguns. With light charges it is easy to double up if you aren’t paying attention. The best way to prevent that is to use a loading block where you can observe all your loads to make sure they all have the same amount of powder. In modern rifle loads there isn’t much air space between the bullet and powder. In a strong gun a couple or few grains of rifle powder won’t harm the gun though it may show signs of pressure. That doesn’t mean that I recommend using over loads because anything can happen per Murphy’s Law. Someone I know well was loading 38 specials with 4.5 X Green Dot with a 148 grain wad cutter. While not the load I would use it is ok. Anyway he shot one and it made a tremendous noise and had very heavy recoil. After we got the cylinder out we saw that the primer pocket was greatly expanded. The empty had to be pounded out. Anyway I pulled a bullet and it had 9.5 of Green Dot. He had set his scales off by a 5 grain notch a mistake by someone not paying attention to what they were doing. The gun was an old model Ruger Blackhawk and I feel that if it was a lesser gun it would have blown up. When a revolver does blow up shrapnel comes out the top and sides. That’s why you never stand along side some who is shooting one. Also particles from the flash gap can injure you by standing along side a revolver shooter. Years ago I used to duck hunt with two brothers who had their own unique ideas on how to load shotgun shells. They always put in extra powder and shot believing that it killed ducks better. They even cut down the wads to make extra room for the other components. The only thing they killed was their guns. I seen bulged receivers and a Browning auto that had the bolt blown half way through the back of the receiver. Trying to talk common sense to them was a waste of time and I refused to sit in the same blind as them because I did not want to get sprayed with shrapnel. It was a good thing that we leased three blinds between the five of us.  Make sure you use the proper primers when loading. For instance using rifle primers in pistol loads could cause a pressure spike sometimes being dangerous. On the other hand using pistol primers in rifle ammo can cause another set of problems one of them under igniting the powder charge. Primers are made to ignite powder under a certain set of circumstances and switching them around can open a can of worms that you don’t want to open. Pistol primers are also softer then the rifle verity which could enable gas to escape into the action causing damage.   

  Among other things that cause excess pressure is oil in the chamber or excess grease in the barrel. It usually won’t blow up a gun but excess grease in the barrel can cause a bulge thus ruining it. I know a guy that always put way too much oil in his chamber after cleaning it. We were shooting and upon him firing his 7 mm magnum smoke came out from the chamber. The bolt was hard to open and the case was stuck in the bolt head. We got it out and the primer pocket had expanded. Upon cleaning his gun the problem disappeared. Excess oil makes the chamber smaller preventing the brass from gripping the chamber walls as normal and also increases back thrust. In a weaker gun it could destroy it.  Old ammo that is stored in a hot place for a long period of time may get stronger and inconsistent. It may not blow up a gun but could cause pressure signs and is very inconsistent. If you have old powder that shows a red dust dispose of it. It is going to be unstable and possibly dangerous. While rare especially with new guns a sharp or too long firing pin could pierce a primer releasing gas in the action. In some cases it could damage a gun or injure a shooter in guns that don’t have good systems to vent gas away from someone. Shooting glasses should always be worn especially with older guns.      Annealing cases is an operation necessary in some case forming. It makes the brass easier to work and prevents splitting the mouths. That’s important when using rare cases or complex forming of some rounds. However you never anneal the case head as that will weaken it causing a failure upon firing. That could damage or destroy a gun. When annealing be sure that the first inch or so is under water and they don’t get real hot. Poor quality guns can blow up even with normal ammo. There were a couple of companies in California that went out of business because of guns blowing up. I personally shot a Davis derringer in 38 special that blew up in my hand. Using regular ammo the barrels blew off cutting my finger. We looked for the barrels for hours but were unable to locate them. I was lucky to get off so lightly in the injury department. I examined another one and found that the barrels had thin steel inserts with the rest being aluminum or some pot metal. No wonder it blew up. I have another derringer obtained from a customer in 45 Colt that blew out the side with normal factory ammo. (See photo) It always pays to spend a few extra bucks and get a quality gun for safety and reliability. This applied to long guns as well as handguns. For the record I don’t like derringers even good ones for any reason.    

 If a round fires before it is fully chambered that causes a really dangerous situation. The gases have to go somewhere and frequently the shooter gets injured. I have a 380 that fired in such a way. You can see a tear in the case where the powder escaped. It blew up the gun (See photo) luckily the shooter wasn’t seriously injured. It was a poorly made weapon thus causing the accident. The firing pin was probably protruding causing it to go off prematurely. I recently purchased 2 rolling block rifles from Sarco Arms. The 12.17 X 44 Swedish had a firing pin that was rusted forward and protruded all the time. If I seated a round in that gun without noticing it the results could have caused me a world of hurt. I always go over all the guns I buy especially the older ones to prevent such problems. When you seat a round in a rolling block the next step is throwing forward the part that holds the firing pin. The momentum could cause the round to go off before the action was completely closed and that has happened in the past.  I saw it and cleaned and oiled the mechanism which freed the firing pin and it now works fine.  A high primer can also cause such an incident so be sure all your primers are seated flush or .001 or .002 below the case head.  I have seen 40 caliber Glocks and a Sig demonstrate this problem. Probably the case wasn’t full body sized causing the round to go off prematurely causing this problem. Commercial reloaders full body size the 40 caliber cases prior to loading. Magma Engineering in Queen CreekAz offers a set up for that operation for the 40 and any other caliber you may want to do that with. While the shooters got sprayed they weren’t injured nor was there apparent damage to the pistols.  Recently a young fellow was hunting with me. He had a 30-06 Springfield and it fired while he was attempting to chamber a round. It went off spraying his for arm with gas and lodging a bullet in the barrel. I found that the bolt was improperly assembled. It was backed off a thread and somehow turned and fired. I could not find anything else wrong with the bolt and upon proper assembly was ok. There was no damage to the rifle though getting the bullet out of the barrel was a chore. Also if you shoot old ammo hang fires may occur. What happens is you shoot and a few seconds later the round will go off. As long as the gun is fully closed no harm is done. However if you are opening up the weapon the unsupported round may go off. That is extremely dangerous and can cause serious injury to the shooter and bystanders. Gas and particles will be sprayed all over the shooter.  Always keep the gun closed and pointed in a safe direction for at least 60 seconds.  I have encountered such ammo in everything from 22 rimfires to old military ammo. This ammo should be disposed of in a safe fashion. I had some old 303 British and 7.5 French that had hang fires. The ammo showed signs of poor storage as well as being old. I pulled the bullets and disposed of the rest. Other odd things that can happen is shooting 9mm Luger in a 9mm Italian Glisenti pistol. The dimensions are about the same but the Luger round is loaded much hotter. If you shoot the Italian gun load your ammo very light, using minimum 9 mm loads minus a grain of powder. Of course you already checked out the gun for soundness and safety at least I would hope you did so. A 38 Super fired in an old 38 auto can produce disastrous results. Why they made the guns to shoot the same size ammo but different levels of performance I don’t know.  That’s why they made the 357 magnum case longer then the 38 special. The 30 Mauser round fired in the Broomhandle pistol can destroy it especially if it’s the Czech machine gun ammo. The much older Broomhandle design isn’t as strong as a new action such as a CZ 52 which can digest almost anything. I have a Carcano that was rechambered for the 8 X 57 and used in Africa during WWll. It looks crude around the locking lugs and other critical areas and I for one would not shoot it with full power 8 X 57 loads. I do shoot it with reduced and cast bullet loads and it is accurate. I have not personally heard of one blowing up but I don’t want to be the first statistic on that one. It also makes an interesting addition to my collection as is. Many years ago Winchester loaded up some 38-40 ammo to some pretty hot specs with jacketed soft points. While it was safe in a model 92 firing it in a model 73 or black powder Colt would cause you to wear that weapon. If you encounter some of that old ammo and are not sure of the strength better err on the side of caution. While it’s not common it’s still around in fact I saw some at a gun shop just today. The old 280 Ross could be fired with the bolt improperly assembled causing serious injury or death to the shooter. Another rarity but may occasionally be encountered and should be kept in mind when buying an unfamiliar gun. There are other examples of old guns that can fire new and hot ammo such as the 38 S & W firing the 9 mm rimmed ammo that Federal made a few years ago for the defunct but hot 9 mm rimmed offered in the Ruger. At the end of WW ll the Japs were making their 7.7 rifles out of anything they could find. They are dangerous to fire and if you find one hang it on the wall. Some clues are wood butt pads and extremely crude workmanship. If in doubt about any gun consult with a qualified gunsmith prior to shooting it. I can not emphasize that point too strongly seeing what I have seen on the market.    

 Happily shooters don’t often get seriously injured during one of these incidents. Part of it is the design of modern guns. Most of them are well designed and made so if a case fails for instance the gas is diverted in a harmless direction. Part of it is dumb luck. Using a little care and common sense will eliminate most accidents.