I bought a Colt M-4 .22 Auto (AR look-alike) for my grandson's birthday. My son and I were supervising him shooting it. We saw or heard nothing out of the ordinary (no squib) until he had an excessively loud round which peppered him with gas/powder (thankfully no physical damage done.)

I found that the bolt was not fully closed and the case still in the chamber with about 3/16" protruding and a hole blown out of the side of the rear of the case.



I find that the bolt will no longer close fully, staying about 3/16" open, and that the trigger will release the firing pin when it is in this partially open position.

It appears to me that the rifle fired with the bolt partially open, causing the blown case. However, upon calling Walther (the manufacturer of the Colt M4), they insist, without examining the rifle, that it had to be the fault of the ammunition. They claim a squib load was fired immediately before the "exploding" one. I agree that there is now a bullet lodged in the barrel (how many is impossible to say without disassembling the gun). But I believe that the bullet in the barrel is due to the gun's firing with a partially open bolt. The Walther representative also says that it could be a a partial case separation from the previous round which prevented the next round from fully chambering -- nope, the chamber was found to be clean and clear once the blown case was removed with the blade of a pocket knife serving as the extractor.

Walther refuses to even look at the rifle, saying that I need to contact the ammunition company instead. I told them that I wanted to send it to them and if they found that the ammunition was at fault that I would pay the repair costs; but they refuse to allow me to do this. Their excuse is that ammunition manufacturers have let their QC go to pot in the recent rush to meet demand, so that MUST be the problem. However, Walther's problem is that I haven't bought any .22 rimfire ammunition in several years. In fact, I know that this particular lot of ammunition is at least 10 years old.

The ammunition is Remington Golden Bullet and is at least 10 years old. Number on the box flap is R04D2B (I suspect that the 04 is code for 2004). Now, I don't think highly of Remington .22 ammunition. But I know when a squib has been fired (and so does my 39 year-old son, and for that matter, 13 year-old my grandson.)

My questions: 1. Has anyone had a similar issue with the Colt M-4? 2. What would you do in this case?

If the Colt M-4 truly will fire from a partially open bolt, then this is a real safety hazard which needs to be addressed.

Update: Walther responded to a pair of emails I sent them, one containing a link to this post. A very nice lady called me and cheerfully agreed to send me a shipping authorization and prepaid label. She did warn that if they found defective ammunition the cause that I would be liable for repair costs. I don't disagree with that policy, but I wonder how likely the technician, who now has a stake in being "right" on his pre-conceived notion that the ammunition was at fault, will be to admit some defect in the gun?

You might be able to save yourself some time and, possibly, money by determining how many bullets are lodged in the barrel.

1. Insert a cleaning rod into the muzzle, push it to the obstruction, mark it, remove it and measure it. That is the distance to the front of the obstruction.
2. Insert a cleaning rod into the breach, push it to the obstruction, mark it at the end of the upper half of the receiver, remove it and measure it. That is the distance to the rear of the obstruction
3. Measure the distance from the muzzle to the rear of the upper receiver.
4. Subtract measurements 1 and 2 from measurement 3. This is the length of the obstruction.
5. If the obstruction is approximately 1/2" long then you only have one bullet lodged in the barrel. If the obstruction is closer to 1" long or longer, then you have more than one bullet lodged in the barrel.

Also, you say it is a "Colt M-4 Failure". If the product is Colt then the description is accurate. However, if it is not branded "Colt" then you should not refer to it as a Colt. After all, would you use "Rolls Royce Spontaneous Engine Fire" to describe what happened to a Rolls look-alike kit car built on a Volkswagen frame and engine?

The guys who compete in the Tuesday Afternoon Schuetzen Verein shoot a lot of 22 rimfires, but from old time single shots and high-end bolt actions. We have experienced squib loads that leave bullets stuck in the barrel, mostly (but far from only) from Remington and Aguila production. We have also seen burst cases, not fired in a blow-back autoloader, but in solidly breeched rifles.

During the summer, we normally shoot European target ammunition, but during the winter, when we shoot at 50 feet, we often shoot whatever is cheap, sometimes Blazers, sometimes the Remington stuff.

Those of us who sweep up after the range has been open to the public find many discarded but presumably loaded 22 cartridges on the cement floor. Frequently these discards are Remingtons.

The rate of failures is inversely proportional to cost. Grenadier's advice is correct. It could be the ammunition.

It is branded Colt and made under license from Colt by Walther. I call it what it calls itself and is so labeled on the gun, the owners manual, and the box. Walther is the manufacturer and guarantor.

I'm not about to disassemble a new rifle in order to get a rod into the breach. Besides, if there are two bullets in the barrel it would be obvious by a bulge on the outside of the barrel, but since the bullet (or bullets) is lodged at a point underneath the handguard, such bulge, if present, is not visible. Again, although it is hardly rocket science to remove the handguard, I am not going to do so. I want to send the rifle back to the factory unmolested so that no question will be raised as to whether I had done something by disassembling it to either cause the malfunction or to obscure the cause of the malfunction.

It is possible that something has broken which allows the firing pin to fall before the bolt is fully forward. However, if its design is such that the firing pin can be released with a trigger pull when the bolt is not in battery then that represents an unacceptable hazard and should either be corrected or the model recalled.

Understood, Colt "owns" any defect in the rifle.

I have seen firearms with as many as six bullets lodged in a barrel, each smashed up against the other, and not visible from the outside.

If there is a defect in the design then Colt and Walther are welcome to hash that out however they might, but it is Walther who manufactured this particular piece and is responsible to me for its performance.

Rimfire barrels almost always bulge in the instance that a round is fired when a bullet is lodged in the barrel. However, if thick enough and hard enough, and especially with low pressure ammunition, then a barrel might very well not show an external bulge. Just how thick or hard the barrel of this particular rifle might be at the point of obstruction is unknown.

quote:

Originally posted by Stonecreek:

I find that the bolt will no longer close fully, staying about 3/16" open, and that the trigger will release the firing pin when it is in this partially open position.

I had an AR-7 for awhile that would do that, maybe because it was dirty but it was disturbing in any case.

quote:

Originally posted by waterman:
The guys who compete in the Tuesday Afternoon Schuetzen Verein shoot a lot of 22 rimfires, but from old time single shots and high-end bolt actions. We have experienced squib loads that leave bullets stuck in the barrel, mostly (but far from only) from Remington and Aguila production. We have also seen burst cases, not fired in a blow-back autoloader, but in solidly breeched rifles.

During the summer, we normally shoot European target ammunition, but during the winter, when we shoot at 50 feet, we often shoot whatever is cheap, sometimes Blazers, sometimes the Remington stuff.

Those of us who sweep up after the range has been open to the public find many discarded but presumably loaded 22 cartridges on the cement floor. Frequently these discards are Remingtons.

The rate of failures is inversely proportional to cost. Grenadier's advice is correct. It could be the ammunition.

No experience with Aguila, but I have found by far the most failures to cycle a semi-auto action occurs with the Remington products. Never saw a bullet stuck in the bore, but plenty of "light" shots with Remington rimfires. However, I've not (previously) experienced a blown case with Remingtons, though it is clear how it can happen with a low-cost mass-produced item like a .22 LR cartridge.

The technician I spoke with at Walther said he had a rifle in the shop currently with a bullet in the bore. Ironically, it he said was Winchester ammunition, which I have found to be among the better of non-premium brands.

The factory warranty repair shops are apparently seeing, or claim to be seeing, an elevated number of ammunition problems with some of the most recently manufactured rimfire ammunition. It stands to reason that more sub-quality ammunition might show up when manufacturers are pushing production to the limit in order to get volume to a starving market. Whether this is actually the case can only be determined by doing a statistical analysis of the failure rate of recent rimfire ammunition compared to pre-scare rimfire ammunition, which would be a daunting task.

Regardless, I know of no (full pressure) rimfire ammunition which will NOT blow a hole in the rear of the case if fired with .15" or so of it protruding from the chamber.

Same thing happened to me a few years ago with a Remington 552 and currently purchased Remington .22 LR Golden Bullets. Action not fully closed, my finger was not on the trigger, and the round went off. Glad I had on glasses and ear protection. No damage to the gun and I never figured out the why or wherefore of the incident.