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BCA bolt action upper for $350? (Page 14 of 21)
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Originally Posted By Capt_Destro: Any of you guys cut your Bolt Carrier with a hack saw?  I don't really trust my self with power tools unless I cut a bit longer than I am planning.  I used an 10,000 RPM angle grinder with a (worn) 4" wheel. I intentionally cut long, about 1/8" past the diameter reduction. That only took like 15-20 seconds per side. I spent about 30 seconds smoothing and evening those cuts with the side of the angle grinder blade. Then I used the side of a shop grinding wheel to grind the flats down and even them out just behind the diameter reduction, taking another minute or so. I used a hand file to chamfer the inside edges of the cuts, and smooth the rear of the bolt tails further, taking another couple minutes. Fine grit paper to further smooth/polish up the rear surface took a several minutes, but that step was part of just polishing the carrier. I wouldn't try to cut with the angle grinder right at the point I wanted the bolt cut at -- too high of a chance of messing something up. ----------------------------------- Topics Covered in Each Page Because repeat questions are getting more common * Discussions of most price changes/sales excluded from index
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Another fun day of playing with the BC10. Ran the new scope and new makers bullets. New scope is another Bushnell engage (I'm up to 6 now and this is the third 3-12). They've got good glass and great turrets for sub $250. Loaded 6 rounds of the 180grn makers rex bullets with titegroup to see where I was at with velocity testing. Was around 950fps so I'll bump it up next time. Did some ballistic water jug testing and at that speed they'll penetrate 3 jugs and stick into the 4th like a throwing star. All opened up to a 1" diameter broadhead and the petals are sharp. Attached File Attached File Did a quick video with the bc10 and subs. It runs smooth.  Bear Creek Bc10 308 subsonic rounds |
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Originally Posted By the-answer-is-42: How are the 'crappy' OEM BCA parkerized/etc barrels shooting? Are they 2-3MOA or actually good with maybe handloads? That's about what I was getting with the factory 223 barrel, even when using BH and Norma match ammo. Swapped out the barrel with a Rainier Arms Ultra Match 11" and it shoots lights out (for me anyway). Running it suppressed The RA handguard I ordered with their barrel did not fit the BCA upper correctly, so I only replaced the barrel and reused the BCA handguard. Has met my original goal to the point I'm going to put a thermal on mine for night time hunting |
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Originally Posted By AL1EN: Hell yeah! Something in the works over at BCA! https://i.imgur.com/KlzQO79.png Might have to do a 9mm or a 45. A 44 mag would be sick. |
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Bolt action - long action (30-06 or similar) ar15 or ar10 style rifle... Interesting... BC-8. Is there such a thing as an AR-8 lower? I never researched it or had much interest. With that being said I have about zero need for an AR style "long action" heavy caliber rifle. I already have long action hunting rifles that fill this roll. |
Originally Posted By ar-jedi:
SO MUCH WIN IN ONE POST IT COULD CRASH ARFCOM !!!
SO MUCH WIN IN ONE POST IT COULD CRASH ARFCOM !!!
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Originally Posted By thederrick106: Bolt action - long action (30-06 or similar) ar15 or ar10 style rifle... Interesting... BC-8. Is there such a thing as an AR-8 lower? I never researched it or had much interest. With that being said I have about zero need for an AR style "long action" heavy caliber rifle. I already have long action hunting rifles that fill this roll. That's a mighty big roll!  Hopefully they'll get into the 'bargain' .50BMG game. 
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Originally Posted By Cycolac: That's a mighty big roll! Hopefully they'll get into the 'bargain' .50BMG game. Originally Posted By Cycolac: Originally Posted By thederrick106: Bolt action - long action (30-06 or similar) ar15 or ar10 style rifle... Interesting... BC-8. Is there such a thing as an AR-8 lower? I never researched it or had much interest. With that being said I have about zero need for an AR style "long action" heavy caliber rifle. I already have long action hunting rifles that fill this roll. That's a mighty big roll! Hopefully they'll get into the 'bargain' .50BMG game. ETA/ too late to edit type  Attached File Attached File |
Originally Posted By ar-jedi:
SO MUCH WIN IN ONE POST IT COULD CRASH ARFCOM !!!
SO MUCH WIN IN ONE POST IT COULD CRASH ARFCOM !!!
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Originally Posted By thederrick106: Bolt action - long action (30-06 or similar) ar15 or ar10 style rifle... Interesting... BC-8. Is there such a thing as an AR-8 lower? I never researched it or had much interest. With that being said I have about zero need for an AR style "long action" heavy caliber rifle. I already have long action hunting rifles that fill this roll. There's a few companies producing large frame receiver (300 win mag) rifles. I suspect there's no standardized form factor. |
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My McGowen .338 ARC barrel is arriving today. I ordered it before I knew these bolt action uppers existed, Dec 5. 2024 (black Friday sale). It was for a straight-pull bolt upper, so the barrel has no gas port or and has a custom contour blending a sporter contour and a target style contour, accommodating for a muzzle device. We'll see how it looks when it gets here. Anyway, even though I had a Spikes slick side upper & side-charging carrier set aside for this build (straight-pull), I decided I'd prefer it on a BCA bolt-action upper. So, I ordered a couple more BCA BCGs & receiver combos -- might as well have a spare and get free shipping-- using on a 10% off code for signing up for text advertising (bleh!), and now I'll wait for those to arrive before I build this out. My original handguard selection had been intended to mate up with a forged upper. I've got a couple options sitting around (Odin Works Rune handguard, Troy X-Series), so I'll see how they matched with the BCA upper when they arrive. I really liked how my BCM MCMR mated with these uppers. We'll see what I settle on. Pics coming as parts come in and assembly starts. Funny thing... when I signed up for text messages from BCA to get the coupon code, the code they texted me, "BCTEXT10" did not work. I scratched my head and added an "A" after "BC" and it did work. Great way to save money, though -- send out typo-ed coupon codes so people get advertising but no discount. ------------------------ McGowen custom 16" .338 ARC 1-8 twist barrel:  McGowen custom 16" .338 ARC 1-8 twist barrel, Griffin muzzle device, Troy X-series rail:  Mock-up with Spikes' slick side, Troy X-series rail, McGowen Precision custom barrel, Griffin Armament muzzle device:  Mock-up with Spikes' slick side, Troy X-series rail, McGowen Precision custom barrel, Griffin Armament muzzle device: 
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Originally Posted By PreacherOfGadget: My McGowen .338 ARC barrel is arriving today. I ordered it before I knew these bolt action uppers existed, Dec 5. 2024 (black Friday sale). It was for a straight-pull bolt upper, so the barrel has no gas port or and has a custom contour blending a sporter contour and a target style contour, accommodating for a muzzle device. We'll see how it looks when it gets here. Anyway, even though I had a Spikes slick side upper & side-charging carrier set aside for this build (straight-pull), I decided I'd prefer it on a BCA bolt-action upper. So, I ordered a couple more BCA BCGs & receiver combos -- might as well have a spare and get free shipping-- using on a 10% off code for signing up for text advertising (bleh!), and now I'll wait for those to arrive before I build this out. My original handguard selection had been intended to mate up with a forged upper. I've got a couple options sitting around (Odin Works Rune handguard, Troy X-Series), so I'll see how they matched with the BCA upper when they arrive. I really liked how my BCM MCMR mated with these uppers. We'll see what I settle on. Pics coming as parts come in and assembly starts. Funny thing... when I signed up for text messages from BCA to get the coupon code, the code they texted me, "BCTEXT10" did not work. I scratched my head and added an "A" after "BC" and it did work. Great way to save money, though -- send out typo-ed coupon codes so people get advertising but no discount. ------------------------ McGowen custom 16" .338 ARC 1-8 twist barrel: https://i.imgur.com/5bTzelY.jpeg McGowen custom 16" .338 ARC 1-8 twist barrel, Griffin muzzle device, Troy X-series rail: https://i.imgur.com/Evh2uBD.jpeg Mock-up with Spikes' slick side, Troy X-series rail, McGowen Precision custom barrel, Griffin Armament muzzle device: https://i.imgur.com/Xf68rT0.jpeg Mock-up with Spikes' slick side, Troy X-series rail, McGowen Precision custom barrel, Griffin Armament muzzle device: https://i.imgur.com/PoWzPJn.jpeg I look forward to seeing your results. I really want to see that 338arc be an easy cartridge to load for and your giving it it's best chance with those parts. |
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I got a 16in 5.56 upper on Monday. I have yet to shoot it but was able to strip it down, weigh components, make modifications, and reassemble. The 16in M4 profile barrel weighed 30oz without the gasblock sleeve and flashider. The sleeve weighed 1.4oz. The upper and bolt assembly weighed 22oz. The 15in handguard without hardware was 9.8oz and the barrel nut was 4.6oz. The first thing I did was make a delrin bolt handle spacer to help preserve the anodizing like others did earlier in the thread. Reattaching the bolt and cycling the action resulted in pretty persistent hanging up of the lugs. So, I stripped the bolt, polished the firing pin while it was out, rounded the cam-pin corners, and dremeled on the bolt lugs' right edges. The small amount of material removed from the lugs ended up making a huge improvement in cycling. The lugs will still catch slightly at times, however applying force seems to allow them to go ahead and slip past each other as opposed to a complete stop that previously occurred. I also drilled a hole down the center of the bolt handle to remove a few more grams. I thought the handguard was surprisingly nice considering the price of the upper. I just wish the barrel nut was a few ounces lighter. To help, I ended up putting it in the lathe and removed 1 ounce worth of material from the ID. The last thing I did was took the included flash hider, turned it down to .750 in the lathe and cut it off so that it sits a little proud of the crown to act as a thread protector. The assembled upper on a regular lower with CTR and spring/buffer still installed weighed 6lb 9oz. My only real complaint at the moment is the same as others - how easy the bolt comes out of battery as I'd like to hunt with this setup. I will hopefully be able to get out to see how well it cycles and shoot some initial groups within the next week and will report back. |
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Welcome to these here parts. Looks like you've worked through the vast majority of issues you can have. Given what you've done, I'll presume you've read quite a bit before diving in. Making a rounded cutout at the rear of the ejection port's pocket for the handle base to rotate down into helps hold the handle in place. I haven't tried an increased strength bolt-tail spring, but combining that with a cutout pocket should help even more. With thick nylon washers oversized appropriately, I managed to get the handle quite snug, too, before receiver modification. I'm about to do another build, and I'm not sure I'll bother to cutout the pocket rear -- the lock with nylon washer solution held shut pretty firmly. Seems like you're on the right track. |
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BCA package arrived: Both upper kits included a 2 set screw shaft collar.  All parts were included in both packages... not that I had any concerns, lol. Now: true receivers, modify and polish carriers and handles, etc. I remember doing this once before. ETA: One of my bolts was marked with "BAS" underneath the carrier key:  ETA 2: After truing the receivers, I couldn't help but notice that the receivers' fronts' machining left drastically different width receiver faces:  One has a width of 0.058", the other 0.090". Both were pretty close to true with no extreme high or low spots. ETA 3: I am PISSED! The two receivers I got (7.62 / 12.7 kits -- not planning on using the bolts) both had alternate ejection port geometry from my last receiver, and it's causing problems retracting the handle because they don't support the carrier's right lower front at all:  This is not what the receiver looks like in the picture on their website. The issues with lug-lock during retraction are much worse. This lack of carrier support is EXACTLY what I was worried about happening when I modified the same edge, but much less than BCA's modified geometry. This isn't something that's "fixable" on the user end. Who else has a receiver with an ejection port that's widened on the bottom instead of flat the whole length? |
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Except for the additional material cutout at the bottom of the ejection port (red box in picture above), my earlier receiver and these two receivers are the same. The two that I got today are identical to each other, with that additional material removed on the lower, inner part of the ejection port. My first one is only different in that it doesn't have that material removed. I think it's an enlarged port for easier ejection of larger cases. It doesn't seem to affect the surfaces that interface with magazine feed lips at all. ETA2: So, apparently there's (at least) 2 different AR-15 pattern BCA bolt action uppers. One with a flat, continuous bottom to the ejection port + charging handle rearward cutout. In the other, there's a bottom cutout that enlarges the port to the point where it removes all bearing support for the carrier during cycling. I think this is why some people are having much worse cycling/retraction issues than others. Question is, which calibers come with which ejection port cuts. I have my first, standard cut one, ejecting .375 SOCOM fine with much more minimal addressing of that edge, and only the Beowulf has a wider case, and not by much. There's no reason for as large of a cutout as BCA has added for their larger bore offerings. ----------------- ETA: Convenient way to keep your spring, firing pin, and cam pin together while working on the carrier: 
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Here's some better pictures that better illustrate this difference Here's my first upper, from a 5.56 upper I rebuilt into my .375 SOCOM. Notice how the surface is flat the entire length (ignoring my own work). This appears to be their standard upper.  ----------------- Here's my upper from the 7.62 / 12.7 kit. I'm guessing this is their big bore cartridge receiver. Notice how the shelf is not continuous, and has a cutout for the ejection port length of this surface.  So, I guess I was wrong many pages back when I said I thought they only had one upper design. Turns out they do have a big bore one. And I'd avoid it, because the depth of the cutout is excessive, as is the length. The SOCOMs have the widest base of 14-15 cartridges, though the Beowulf is within a few thousandths and maintains that width longer. If the standard upper can cycle SOCOM rounds with just some edge rounding, there's really no need for a deeper cut, especially given that it removes support from the carrier while cycling. To avoid cycling issues, I would recommend to anyone reading this that that they use the 5.56/.300 blk/.350 legend upper+BCG kits for large bore builds, and supply your own bolt. If the port door needs widening for ejection issues, address it yourself. The difference in how it tolerates "imperfect" handling of the bolt handle for cycling is HUGE -- the 5.56 upper design allows for much more robust operation. Additionally, adding a cutout for the rear of the carrier to lock into becomes even more problematic with the enlarged port door uppers due to the material removed from the bottom of the port door. |
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Damnit, that means that it's quite likely they all are that way now. Wonder when they changed over. The difference in cycling, and the difference in the efficacy of the various solutions, is quite notable between them. It's BCA, so you gotta wonder if they just happened to have more of the large bore one on hand, so that's that they used to make some 5.56s, or if it really is all of them now. Ugh. |
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Originally Posted By Speedy7722: My 5.56 upper that I recently received came with that extra bevel/cutout in the ejection port. I did get out to shoot it this weekend at a group range day. Only shot out to about 50yds and got a rough zero on it, but as far as function with an assortment of .300blk ammo I had, it ran great. Subs sounded excellent with the old AAC can as well, tons of fun to shoot.   |
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Originally Posted By AL1EN: I want to do a bulpup 9mm. |
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I hope to get out today or tomorrow for an initial sight in with the .338 ARC. With all the rain, power outages and flooding in the area over the weekend, combined with my schedule, it hasn't worked out yet to get to a range yet. I'm gonna take it with me to the indoor range -- outdoors are still soggy as hell -- when I shoot some 9mm and get a 14 yard zero with AAC 300 grain subs, which should put me close to my 100 yard zero when I get it to an outdoor range. That said, I did a pair of 8 yard test shots, so I know: it shoots, it's quiet subsonic, and my two bullets went through the same hole at 8 yards. ------------ ETA: Here's the build, as assembled:  McGowen barrel Griffin taper mount ez-muzzle brake (.338 Paladin taper mount brake is on order) Cryptic Bolt BCA upper + carrier Griffin 1-10x optic & Griffin mount Troy X-Series handguard Magpul MOE QD M-LOK bipod WMD Buffer Tube (NiBx) Vism stock (nicer than I expected) RGuns lower Griffin 2 stage adjustable trigger Lower small parts randoms from parts container Oh, funny aside, when I went to test fire it: "click". I found the firing pin had a broken tip. I'm not sure if that was a BCA pin or one I had sitting around with the bolt, but either way, it was never used, so I'm thinking manufacturing defect. Glad I found that before getting to the range. Also goes to show that having some spare parts is good, even if you don't give your guns heavy use. |
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Originally Posted By Outrider: Alright, I think I'm going to jump down the rabbit hole of a .300 BLK build. I have a Ruger American Ranch that feeds like garbage. I think I can pull a BCA build together without too much of an investment. |
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Originally Posted By VTD: Don't expect a silky smooth action from these. I had to do some serious filing before mine fed half as smoothly as my Ruger. It doesn’t need to be smooth, I’m just looking for it to feed/cycle reliably. The Ruger isn’t very smooth either but rounds slamming into the breech face piss me off. |
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Originally Posted By VTD: Don't expect a silky smooth action from these. I had to do some serious filing before mine fed half as smoothly as my Ruger. Originally Posted By VTD: Originally Posted By Outrider: Alright, I think I'm going to jump down the rabbit hole of a .300 BLK build. I have a Ruger American Ranch that feeds like garbage. I think I can pull a BCA build together without too much of an investment. On the plus side it doesn't sound like a zipper. I had to smooth the hell out of my American Ranch |
| I got my 300 BLK upper in today and immediately took off the barrel and handguard. I’m going with a 6” Faxon and want to try a PRI clone rail and tuck my can ala the McMillan C5. I changed the bolt to a chrome one and replaced the firing pin and cam pin. I’ll probably try a POF cam pin. I did lightly sand and steel wool the carrier key and that did seem to make a big difference in smoothness. I fired a few rounds in the backyard to confirm feeding/extraction and it seems solid. I’m excited to keep the project going. |
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Originally Posted By bendigo78: @PreacherOfGadget Have you gotten that 338arc out yet? So, after way too much delay, I got out to get that 14 yard zero (for a 14/100 yard zero) with AAC 300 gr HPBT. Now I need to get out to a nice outdoor range verify/fine tune the 100 yard zero and do some longer shooting. While setting the 14 yard zero I stacked most shots on top of each other, so I'm feeling pretty good about what it'll look like at 100. I gotta say, 338 arc subs are really gentle shooting and quiet. It was far and away the quietest of what I shot today, including .300 blk semi-auto, 9mm semi-auto, and this .338 ARC bolt (all using the same 9mm suppressor). As far as recoil, it seemed gentle; quite comparable to .300 blk. The target barely moved in the crosshairs upon firing. |
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Originally Posted By PreacherOfGadget: So, after way too much delay, I got out to get that 14 yard zero (for a 14/100 yard zero) with AAC 300 gr HPBT. Now I need to get out to a nice outdoor range verify/fine tune the 100 yard zero and do some longer shooting. While setting the 14 yard zero I stacked most shots on top of each other, so I'm feeling pretty good about what it'll look like at 100. I gotta say, 338 arc subs are really gentle shooting and quiet. It was far and away the quietest of what I shot today, including .300 blk semi-auto, 9mm semi-auto, and this .338 ARC bolt (all using the same 9mm suppressor). As far as recoil, it seemed gentle; quite comparable to .300 blk. The target barely moved in the crosshairs upon firing. When you don't have to worry about the volume of gas to cycle actions, you can make some fantastic puff loads. That 308 is one of the most fun guns to shoot. My testing and gun projects have moved to the back burner for atleast 6 months. Depending on the inspection tomorrow, I may have bought a gun range with a house on it. Boxing up 25 years of gun autism is mind boggling. There's atleast a thousand pounds of projectiles. |
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BCA bolt action upper for $350? (Page 14 of 21)
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