Out of curiosity have you guys tested other bolts as well?
Well, I know the answer is yes, are you able to disclose the same data for the other bolts tested?
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I have tested a lot of bolts. I had to pick which design to use for the AAC uppers. No, I can't compare them, but it was useful to make sure we got the best ones.
Hit the nail on the head.
As for the CMM cost comment: I don't see how any CMM sampling is 'inexpensive.' Even laser CMM's like the Faro and Nikon's I have worked with require a dedicated operator and some time for set-up. We would utilize them for developing our X bar and R charts, but 100% sampling is unheard of in high volume manufacturing. The best bet you would have is utilizing vision systems (i.e. a $18k Cognex camera), but even then you're looking at insane amounts of camera investment and requires the attention of a full time engineer. So you're stuck at batch sampling first and last offs if you're operation has it's **** together. Which if you're doing this and have a competent QC staff, you're on par with any 'world class manufacturer.'
Quality control isn't rocket science and I know any manufacturer is capable of it. That being said, I would only trust a manufacturer with a tainted track record if they would be transparent in their QC process. Specification control (finished material qualitites, dimensional), supply chain control (active inventory level management, quality of distribution).
Forgot to mention: the most important part of a successful QC department is developing a relationship with a customer. We always hosted our major customers, showed them our processes, let them have input on what they thought was most important to them, then co-developed our processes and standards with them. That is the only way you're going to sell to your target customer. Now, it's up to your management when it comes to transparancy (how much you want to hate your life) of current production. In the end, your customer will see your product, it's just a question of how well you trust your personnel to react to situations that may be caught in the supply chain.
Bushmaster doesn't 'play the game' with m4c's community. That's what I saw before I purchased my Colt. And, in my opinion, m4c maintains it's credibility through it's moderators, ind. professionals and it's subject matter experts.
My apologies to all on this forum. I posted the following which is incorrect-
The proper way to verify torque is to set the torque wrench to the correct torque and tighten.
Total torque of the gas key bolts is 55 in/lbs + torque from staking. Specification for torque + staking is 55 in/lbs - 100 in/lbs. Verification would require setting the torque wrench to the nominal torque, which is halfway between minimum and maximum. That would be 77.5 in/lbs. Rounding up to 80 is acceptable. Apply 80 in/lbs of torque after staking to verify final torque.
After posting, I realized that re-torquing a staked bolt is an unacceptable procedure. One, there is a risk of compromising the mechanical lock feature of the stake. Two, if the staking is on the minimum side, it would be possible to over-torque the bolt. The proper way to check the torque of a staked bolt would be to break torque, then torque using the proper procedures. It's been a long week with too little sleep
Thank you and again, I apologize for any inconvenience this may have caused