Did your T91 upper run flawlessly? I've got some questions (Headspace issues)

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darkest2000
II
Posts: 19
Joined: Thu Jun 01, 2017 4:31 pm

Hello guys,

I noticed that there may be potentially some head spacing issues with the Wolf uppers, it all started when my buddy's upper would not run (he could only get 3 rounds off before it started to malfunction and would have to kick to get the bolt to open).

Since I've not fired any of mine yet, I decided to check the head spacing on all 3 of my wolf uppers. And to my surprise, none of them would close on a GO gauge.

In fact, I also experienced difficulty closing the bolt on either a dummy snap cap or an actual cartridge, there's noticeable resistance, I can definitely see how this could cause malfunctions.

If I swap out the bolt with a standard AR bolt, then they all head space correctly and will chamber and eject smoothly as well. So to me it's not the chamber or the barrel extension, but the bolt that is the issue here.

I find it hard to believe that all 3 of my uppers would be defective unless Wolf is systematically putting in the wrong bolts in their uppers. (it is known that the Bolt for the military T91 and the original T65 do NOT interchange and they even have warning stickers on the guns that state so in bold letters).

That said, consider that there are so many videos of people test firing their uppers seemingly without issues on Youtube, it baffles me even more. I suppose head spacing issues may not always be apparent during live fire and continued firing may actually "break in" the bolt, but there is a least one video of a guy that claims to have a similar problem with feeding and extraction.

I guess what I want to know is if any of you guys (especially those of you that have already fired yours) can actually check your headspace and share the results?
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Arkane
C
Posts: 150
Joined: Tue Jun 20, 2017 12:35 pm

I initially had problems hand cycling Magpul dummy rounds when I received my upper. Once I flushed and scrubbed the chamber and BCG and gave it a light coat of clp it went better. That chamber, locking area, and bolt HAS to be clean. Prior to that it wouldn't pass GO. Once I cleaned it it closed fine. 500+ rounds of PMC 62g through it so far with no issues.

For SnG this morning I pulled out the mic and compared an unfired A1 bolt to an unfired FN bolt. The measurement from the lug above the ejector measured out @:

Wolf:
Length: 7.08mm

FN:
Length: 7.02mm

With the T65 bolt lugs being 1mm longer I think it's safe to assure we're not getting those installed.
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blueeyedwolf
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Posts: 19
Joined: Sun May 21, 2017 12:14 pm

Please follow this LINK for cleaning reference.
Once you cycle through the steps, please repeat the process several times.
Initially Wolf A1 upper needs an intensive cleaning, once you received it - prior to shooting, especially focus on the chamber area.
For me, I take apart the BCG and clean each part of it with hot water and soap. Dry all BCG parts with compressed air, then lube it very well.
In my recent shooting experience, my BCG seized, so I lubed up the BCG and bolt stop with Dupont Teflon Silicone Lubricant instead of oil. I was really freakin' pleased with the results afterwards, out shooting this morning to trial the Teflon Silicone versus oil, after around 200 rounds noted the weapon working flawlessly. Temps 95 degrees and the barrel was hot couldn't touch it!
FYI, my target group at 200 yard was just as well as the gentlemen next me who were using AI long range rifle. @onion9@
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