Dear American Rifle Company customer:
You are receiving this message because the Archimedes action that you have just received from us or will receive very soon has a minor problem that we must remedy. If you have not received your action yet but have paid for it in full, shipping will be delayed by about five to seven business days while we correct the problem.
So what’s wrong.
The bolt shroud locking pin is not disengaging the bolt body making it difficult to close the bolt. This is because the bolt body is missing a helical relief cut. See Figure 1. The Archimedes prototypes did not require this cut because they did not have closing cams machined into the forward end of the receiver. Since prototyping, we decided to incorporate 0.050” of forward camming to aid in closing the bolt over tight or slightly oversized brass. Unfortunately, we failed to include the helical relief cut that enables the bolt shroud to disengage the bolt before bolt rotation begins. The action will work without the relief cut but the effort required to make it work depends on the relationship between the cocking piece and the trigger assembly. A relationship that does not cock on close might seem to work fine but one that does cock on close will require a forceful push forward to close the bolt.
The fix is very straight forward, but it does require you to send your bolt to us so that we can replace it with one that has the relief cut. We will email a shipping label to you making the return process as painless as we can. You can also simply remove the bolt should locking pin and its spring, but we don’t recommend this because do so will allow the bolt should to easily rotate when the bolt is retracted. We really want you to send your bolt back to us so we can take care of this properly.
We have also noticed that the aft end of the Archimedes bolt may be rubbing the upper sear of some triggers. Thus far, we have very few confirmed occurrences of this, one of which was with a Tubb T7 trigger, but we will be reducing the diameter of the aft end of the bolt by about 0.020” thus adding an additional 0.010” of clearance between the bottom of the cocking piece and the top of the trigger assembly, most likely the upper sear. A bolt having the reduced aft diameter has already been successfully tested for strength.
Lastly, as some of you have already noticed, the cocking piece of the Archimedes is engraved with a couple of number, such as 780/055. These signify some important dimensions of the cocking piece that will enable us to offer you variation that will improve (depending on your preference) your tactile experience when closing the bolt. Most of our customers seem to prefer smooth and bump-free bolt-closing rotation. It’s worth noting that an action exhibiting bump-free closing will not cock-on-close at all. However, nearly all major brands of bolt-action rifles cock-on-close and do so for a very good reason, it improves ignition reliability while reducing the effort to open the bolt. But the heart wants what it wants, and we aim to deliver what it wants. Therefore, during testing, we determined that sear interface protrusion of 0.055 inches (see Figure 2) will result in bump-free bolt-closing when used with Remington, Trigger Tech, Timney, and Jewell triggers. This may not always be the case. We know triggers vary, even triggers of the same type from the same manufacturer. The parts of the action also vary. Thus, if you happen to be using a 780/055 cocking piece and a trigger from one of the aforementioned companies, and you are experiencing some cock-on-close, you can replace your cocking piece with one having 0.010 or 0.020 inches less sear interface protrusion, 780/045 and 780/035 respectively. We are offering various cocking pieces so that you can time you action without having to grind either the cocking piece or sear. We currently have cocking pieces with having sear interface protrusions of .035, .045, .055, and .065 inches in stock. That will likely cover all of the popular triggers but we will make more sizes if necessary.
One of our customers recently sent his Archimedes action back to us along with his Bix’n Andy Tac Sport Pro trigger. We found that a 780/035 cocking piece was necessary to provide bump-free bolt closing.
As we learn more about trigger-cocking piece compatibility, we will compile data and make it available on our web site.
Oh yeah, and there’s one more thing. If you have received a long action Archimedes, we will be sending you a new Picatinny rail for it. We screwed up one of the recoil slots. No need to send your defective rail back to us. Keep it as a back up or just keep using it and keep your new one as the backup. We will continue to send long actions with defective rails to get you shooting sooner than later. We’ll send the new rails as soon as we have them, probably within the next month or two.
Sorry about the speed bumps. The absence of the helical relief cut is really the only major issue and correcting that is our number one priority. We seriously appreciate your business and apologize for the inconvenience and delay these issues may cause.
As always, thanks for your business, support, and interest in firearms.
Sincerely,
Ted
President
American Rifle Company