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Old 10-16-2018, 11:42 PM
s11033 s11033 is offline
 
Join Date: Oct 2013
Location: Boston, MA
Posts: 192
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An update guys:

I’m making good progress toward placing an order for barrels. I’m talking to a couple manufacturers that will work with quantities of 5-10 units, which would be much more favorable than Criterion’s 25 barrel minimum. I’d feel perfectly comfortable ordering those all short-chambered for 6.5x55 rather than resorting to my “half-baked chamber” idea. Hopefully I’ll be able to post some price estimates soon to see what you guys think.

I received one of the sporter 03-A3s that I bought for prototyping and have a second on the way. This first one was blued at some point. But it doesn’t have any holes through the receiver, and the rear sight is intact. I’ll be building an A3-style rifle with it. The one that’s on the way has a Redfield Jr. scope mount on it, and I plan to use it to build an A4-style rifle with an Accumounts PE replica 4x scope.

As soon as I got the rifle, I started tinkering with it and quickly ran into a problem. The 6.5x55 cartridges stack funny in the ’03 magazine because the Swede’s taper is much more extreme than the 30-06’s. It worked fine when loading 4 rounds, but the 5th would occasionally hang up against the rear of the magazine and the bolt would ride over it without catching the rim. I thought about making a magazine insert, but I decided to try something easier first.

I replaced the ‘03 follower and follower spring with the respective parts from a Swedish M96 Mauser. The M96 follower has a taller ridge, which I think keeps the cases properly aligned in the magazine. The spring is stronger than the one that was in my A3, and I think that the upward tension helps keep the rims properly seated against the feed lips so that the bolt never rides over them. With those parts installed, the feeding was 100% reliable.

The follower looks a little odd because it’s shorter in length than the magazine, but it naturally aligns itself against the rear of the magazine. The only time it will go forward is when the bolt is pushed forward on an empty magazine. When a case is inserted the follower naturally returns to its rearmost position under spring tension. The magazine cutoff still works as long as the follower is in the rear position when the cutoff is engaged. The follower can be forced forward past the cutoff, requiring the cutoff to be disengaged, but you’d have to be trying to do that. I don’t think too many of us use the cutoff anyway.

Overall, I think that using the Swedish parts is a cheap ($15) and easy fix to an otherwise complex problem. It seems to have no impact on operation unless for some reason you need to be able to engage the magazine cutoff immediately after pushing the bolt forward on an empty magazine.

The next problem that I’m working on is that for some reason the extractor claw will occasionally fail to grab the 4th case that was loaded into the magazine. I have no idea why it only happens on the 4th, but I do think it’s signaling a problem with rim thickness. I measured a Swedish M96’s extractor claw and sure enough its groove is about 0.25 mm wider than the ‘03’s. This makes sense because Swedish-spec 6.5x55 has a rim that’s 0.3mm wider than the 30-06’s. I tried installing the Swedish extractor on my ’03 bolt and interestingly it went right on. Unfortunately it’s less than 1 mm too wide top to bottom to fit into the receiver.

I have a few ideas on how to tackle this. First I’ll try replacing my ’03 extractor with a fresh one. It may just be out of spec as I can see some areas that are worn. If that doesn’t work, I can see that the 03’s extractor has some metal added to compensate for the slightly thinner 30-06 rims. I can try filing a little bit of metal out of the groove, as I think that would leave about the same amount of metal as the M96’s claw has. If for some reason I’m worried about the strength of the claw, my next idea is to mill or file a tiny amount of metal off the Swedish M96 extractor to allow it to fit the ’03 receiver. I’d like to avoid this as M96 extractors are probably heat-treated and are a bit pricier than the magazine parts I used to solve the feeding problem. Hopefully a fresh ’03 extractor will do the trick.

As an aside, I ordered a reproduction 03-A3 stock set from Sarco just to see how it compared to the CMP set. The barreled receiver dropped right into the stock. The bedding appeared to be accurate and solid, there was good clearance around the barrel, and there was strong (if not slightly excessive) upward tension on the barrel at the front band. I think the stock will require very minor fitting. The trigger guard almost dropped in, but I have to take about 1mm of material off the rearmost surface because the lower stamping of the trigger guard contacts the wood. I’m not an ’03 expert, but the profile of the stock didn’t seem fat or off in any way. I wish I had my USGI A3 and A4 here to compare.

The stock appears to be stained but not finished and leaves some orange residue on the hands. But the wood has clearly been finely sanded and will provide a good starting point for a nice finish with Fiebling’s, BLO and Tom’s 1/3. It’s a nicer surface than the CMP replacement Garand walnut stocks. Unfortunately some bonehead packed a barrel in the same box as the stock, and it was able to bounce around freely, gouging the wood pretty badly in the C-grip area. Hopefully Sarco will make it right, either by replacing it with a new stock, or by offering me a good discount to keep this one and fill in the gouges while I’m refinishing it.

Anyway, that’s all I’ve got to report. Let me know if you guys have any better ideas regarding the extractor issue.

Steve

Edit: Sarco replied first thing this morning to the email I sent them yesterday. They’ll be replacing the stock with a new one, and they’ll be paying for shipping too. I’ve consistently had good experiences with them.

Last edited by s11033; 10-17-2018 at 09:30 AM.
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