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My Razor Magnum build (pics)

18K views 147 replies 18 participants last post by  tanakasan 
#1 ·
Well, when I heard that Select Fire was making a revised version of the 10/22 Magnum I was instantly intrigued. So I called my brother, who has more firearms knowledge than I do, and asked if he thought it would be a doable project, he was very encouraging, so I started ordering some parts.

What I wanted was a heavy barreled semi-auto 17hmr. I'm hoping that the Select Fire receiver will be a good platform to pull off the 17hmr. I have a 10/22T that I replaced the trigger group w/a Kidd, so I already have an extra trigger group. I wanted a stainless fluted barrel w/a laminate stock. Finding a barrel proved more difficult than I expected, so ended up w/a blued non fluted .920 barrel from E.R. Shaw. I ordered a laminate stock from Stocky's, they called a few days later and told me they were out of stock, but could back order it, I said no and ordered a Hogue magnum .920 stock. I ordered a power custom magnum hammer spring, the rest of the parts came from Select Fire (buffer, pins, v-block). I also ordered the fixture and drill bit kit from Select Fire, and a 11/16" reamer from Grizzly.

Cost breakdown......All prices are to the door
receiver kit (w/bolt), buffer, pins, v-block, fixture, drill bits.............$390
Hogue .920 magnum stock............................................................$85
E.R. Shaw .920, 18" 17 HMR barrel, blued.....................................$132
Trigger Group, already had as spare...............................................$000
Power Custom hammer spring........................................................$13
Grizzly 11/16" reamer....................................................................$16
................................................................................Total.............$636

I hope to get the receiver finished on thursday, more pics to come.



















 
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#95 ·
I was able to get the bolt finished last night. I didn't have a scale to weigh the difference. The bolt was also faced, the headspace is now .047. I may be able to get to the range tmrw. Sorry about the pics, I left my digicam @ home, cell phone was all I had.











 
#97 ·
The rear of the bolt is untouched, it's just a crappy pic. The bolt was channeled, then then replaced with Mallory metal, then surface ground flat, which is why it looks shiny.

A few notes on the bolt project: Mallory metal is hard, and requires a carbide end mill to cut it, the bolt is hardened, so a surface grinder was used to channel the bolt (to save on tooling). The melting point of steel and Mallory metal are very different, steel is around 2000*, the Mallory is around 7000*, which makes tig welding them a challenge, but do-able. Apparently Mallory metal is a powdered metal, because there were no tooling marks on the piece that I had (there were no signs of it being cut off of a longer rod), so I guess that it's pressurized into 1'x1.25" pieces.

I'm going to go to the range today and see how she does with this round of experiments.
 
#98 ·
I took it to the range today, and after 350 rounds of testing, I discovered that I need to do more testing. I tried many different combo's of spring length and diameter. But what I found was that it needs to be cleaned a lot, I'm thinking about every third magazine. By the time I realized this I was running out of ammo. So far it seems to like CCI better than Hornady, but I didn't have enough CCI with me to verify that. The next time I go to the range I will take 200 rounds CCI, and 200 Hornady.

I wasn't able to weigh my bolt after adding the Mallory metal. But my current setup is the .040" spring that's about 1/2" shorter than stock, my heavy bolt, and a heavy/long follower. I tried using a piece of the .035 spring and a piece of the .040 spring, but that keeps the bolt from cycling when using a long follower (because of the splicer/connecter).

I think I underestimated how much this thing really needs cleaned. I fought with it for hours (I spent 4 hours at the range) before I noticed the relationship of clean/dirty cycling. When I say clean, all I did was run a boresnake through it, and it would cycle good for about 3 mags, then I would fight with it. I started off with the 20" barrel, then after fighting with it, I swapped to the 18" barrel (which was clean). It started running better instantly, I thought I had it figured out (or really close), then I started having as much trouble with the 18" as I did with the 20". I cleaned it, and it started working better again, then would get worse.

So now I'm not sure if the 18" is any better than the 20", but it was in that swap that I noticed the clean/dirty issue.

I started off with the factory spring, my heavy bolt and long follower...it kicked the extractor out on the 2nd shot. But it never kicked the extractor out again, so the heavier (.040) spring helps that problem for sure. I also put a Kidd buffer in it.

So that's where I'm at now, I need to pick up some CCI ammo, and get back out. Hopefully I'm getting close to getting it sorted out.

Robert, thanks again for the spring, I think it is a much better spring for a .17 HMR vs. the stock spring. I may need to play with length a little still, but I don't think the stock spring will operate a .17 reliably at any length.
 
#99 ·
Progress! Yes!:bthumb:

Glad the spring helped. I am near that same point. The heavy spring was too much. I did try a 8" piece of med spring and it seemed to cycle fine, no extractor issues. but every case was bulged. I am looking at a little lighter next...maybe 7" of med with a new long follower with a 1" long large section. and 2" long spring section. Mines lead filled and weighs an ounce. What length is your current spring?

Are you shooting FMJ or the ballistic tipped ammo? Reason I ask, I read here that the FMJ might cause cycling issues and thats what I was shooting when the case blew out, I believe due to a OOB condition. Or a dirty chamber issue...

Is the 17HMR that dirty? Does a lot of junk come out on the patches? Is 22WMR less dirty?

G/L!

Robert
 
#100 ·
My current length spring is about 6.5" of med. weight spring. I was using mainly Hornady ballistic tip, but I did use some CCI fmj. I need to get more CCI before I head back out. I'm not sure if 22 mag is any dirtier, but I noticed considerably more ejection problems at the end of the third mag (after cleaning the bore). But either way, I had a lot of case bulges, but the Hornady bulged considerably more than the CCI. I had a rim blowout once also (Hornady).

When you take yours back out, clean the bore, shoot until you have trouble, clean the bore again, and see if it straightens out.
 
#101 ·
Well, I stopped and picked up a brick of CCI 20 grain ammo on the way to the range. I cleaned the bore before i started shooting. The first mag went perfect, The first round of the second mag was a fte, I cleared the jam, the rest of that mag went smooth. The third mag went perfect. On the fifth round of the fourth mag I had a case explode, which in turn blew apart the magazine, sending a lot of powder back into my face, thankfully I was wearing eye protection (i have gotten a little gun shy w/this thing).





 
#105 ·
I honestly don't know where to go from here. I guess I could try to add mass to the handle. I'm going to order a couple new mags, but I'm open to suggestion on where to go from here.
I am going to fab one when I get back in town.

Not sure how much can be added and if that amount will help. I guess that a 22WMR is the next direction if we cannot sort this out! Blowing up mags can get expensive...I have one just like that. At least you got many 100's of rounds out of yours.:mad:

@Guitdolin, I *thought* your 22mag was shooting/functioning reasonably well? You might be holding all the answers now!

Robert
 
#104 ·
Your probably right. This thing has been an absolute money pit. By the time you factor in all the time and effort, parts and ammo that I have put in to it, I would have been better off buying a VQ. I did learn a lot, and I like the idea of a semi auto .17, but I think it's about time to punt. I'm going to tinker with it just a little bit more, then put a 22 mag barrel in it.
 
#106 ·
It would seem to me that you guys have done more than your share of work on this project and it keeps biting you in the wallet. I had one semi-auto 17 HMR that for years ran just perfect than it started to go south on me. I have no idea why, I checked the springs, the weight, kept it clean but it would pop a rim just about every 25 rounds or so. It wasn't a 10/22 and it had mags that would just blow out the bottom with little to no damage. The problem with that one rifle may just be that it's worn out -- a lot of ammo has gone through this one -- and I don't want to go back in and rebuild the whole thing. With the advent of the new 30gr V-max 22 magnum ammo, I decided to convert the rifle over to 22 magnum. I don't mean to poop on the project -- it most likely can be done but it would seem that there must be too much variation in bolt and receiver combinations for all the Razor Magnum setups to work with 17 HMR. From what I have seen, only OMR has had luck with 17 HMR and that is not a good percentage. You guys have done some fine work and made note of some very important facts about building and working with the Razor Magnum.
 
#108 ·
I posted these pics in Tanakasan's thread, but I figured I would update mine as well. Here are a few pics of my bolt mod. I removed a section of about 3/4"x3/8" and replaced it with Mallory metal, then surface ground it flush and had it welded in. According to OMR, the stock bolt weighed 203 grams, my bolt now weighs 239.5 grams. So far it hasn't seemed to help, I still have Kaboom's and bulged cases.

This project has turned into a "safety glasses mandatory" kind of thing.

Anyway, here are some pics.

















This last pic shows why my attention has shifted recently.

 
#110 ·
The steel bolt was cut using a surface grinder to save on tooling costs, because it's hardened. The Mallory was cut with carbide. I have only been able to find the Mallory in 1.25" long by 1" round pieces. I called some local engine building and crank balancing shops, they all told me it wouldn't be found locally. You can make a follower with it, bit it would only be 1.25" long. I don't think that would be a great use for it because you can make a 2.5" (or so) Stainless follower for less money, and be similar in weight. I think the Mallory may be a good option on the bolt handle because it can be short and fat.

I think that Mallory is a powdered metal, and is probably only made in short lengths. Mallory is only used (to my knowledge) for balancing crankshafts, where short round pieces are all that will fit. If you choose to weld it, it's melting point (I'm told) is around 7000* vs 2000* for steel, so that can be tricky, but doable. Though I would recommend a tig welder.

Here's a link to the guy I bought mine from on Ebay.

http://cgi.ebay.com/ebaymotors/HEAV...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
 
#114 ·
Just when I was about to lose hope on this project, Tanakasan (Robert) was kind enough to send me his modified bolt handle. When he first offered it to me I was excited, then discouraged when he reported still having trouble with his heavier bolt handle. But I went out to the mailbox today and the bolt handle had arrived (thanks again Robert), so I decided to put it together and go to the range since I had the day off.

Here are some pic's of my rifle with the modified bolt handle.







Long story short, my rifle is shooting great. My total mass with the long follower, modified bolt and handle is 317.5 grams. I am using a 6.5" long .040" top spring (thanks again Robert) an 18" Butler Creek barrel, Kidd single stage trigger, and Kidd 10% heavier main spring.

I put 150 rounds through it, cleaning with a boresnake every 50 rounds, with no kabooms, and maybe 10 fte's. I decided to try the factory 7" .035 spring and it worked good, but the cases were bulged more.The cases were bulged with the 6.5" .040" spring, but very slightly.

Here are some pics of the cases. This pic is of the brass from the .040" spring with CCI 20 grain ammo.


This pic is of the 7" .035" spring using CCI 20 grain ammo.


Then I decided to try Hornady 17 grain ammo, it didn't like it at all. In 50 rounds I had 2 stovepipes, 7 or 8 fte's, no kabooms, but the cases were more bulged than the CCI. This is with the 6.5" .040" spring.



 
#115 ·
I then switched back to the CCI 20 grain and shot 50 rounds flawlessly. The CCI works much better, maybe because it's slower at 2375 fps, maybe the cases are thicker, I don't know. But I never had a single stovepipe with the CCI.

In total I put 350 rounds through it today without catastrophic failure. At this point I think the rifle is working fine, as long as I use CCI 20 grain. I now have about 1200 rounds through the rifle, and I think I may be seeing the light at the end of the tunnel. I will probably just leave it alone for a while and shoot it how it is, although I still don't trust it enough to shoot it without safety glasses. Also, I'm still curious if it might work a bit better, or bulge the cases less If I made a bolt handle out of Mallory metal, I think Mallory is heavier than lead. But my guess would be it would only weigh 20 grams or so more than it does now.

The bulges in the cases now are so minor that I don't think it's a problem. I will take it back out more in the near future and see how she acts, but I'm pretty happy for now.

Again, Many Thanks go to Robert, he really helped me out...Brian.
 
#117 · (Edited)
Oh yeah, the bolt handle that Robert made is MUCH more comfortable than the stock S.F. handle.:bthumb:
Yes, I noticed that also!:bthumb:

Glad its working out for you! Your total mass is only 15g more than mine...does it make that much difference? I even cut my barrel down to 16" and still bulged and 2 blowouts. Many different springs too.

Lead is 1-1/2 times steel and mallory is double-ish. I was unimpressed with my v2 lead filled bolt handle. Only gained a few grams by drilling out steel and back filling with lead.

Well, glad your rifle is working reasonably well now!:AR15firin

Robert
 
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#118 ·
I know this works for setting one up for .22 Magnum ammo, but it won't work for a .17HMR conversion.
The 22WMR Razor functions fine AFAIK.

Brian's is a 17HMR that is running reasonably well now. That is my goal also, a 17HMR. The 22mag barrel I ordered is a plan "B" for me. I don't anticipate much trouble making that one shoot as it has already been done numerous times on the SF site per Phil.

I am going to try just the 1-1/2x guide rod spring as you have used, but with the 17HMR...will LYK what happens!:eek:

Robert
 
#119 ·
I'm going to tinker with it a little more. I ordered another slug of Mallory metal, and I'm going to make another bolt handle. Since the slugs come 1" round by 1.25" long, I'm thinking about making it about .5/.75" round and 1.25" long, with the long side vertical. Basically it would resemble a broom handle, but 1.25" long and radiused on each end. I think that would add considerable weight.

It's working very good now, but it does have occasional stovepipe, which I'm assuming is still bolt speed. And it seems ammo picky. So my hope is that with a little more mass, the rifle will be a little more functional, with any ammo used.

The Mallory metal will be here next week, so hopefully by next weekend I will have the new handle made and able to experiment a little more.
 
#121 ·
The good news about us adding weight to make our rifles work in 17, is that it also benefits the 22mag barrel. So if you get tired of fighting with the 17, one quick swap puts you back to a safe, reliable rifle. Then when the boredom sets in, swap back to the 17 and go tinker, lol. Congrats:bthumb:
 
#122 ·
^^All true!:D

WMR is easy...all the R&D towards the 17HMR helps a bunch. Your HMR build is a lot futher along than mine. Sounds like its *really* close. Hopefully the mallory handle will kick it into the endzone.

My WMR just shoots. No issues, no drama. Itching to see how your mod works so I can copy them!

I still have the HMR barrel!:bthumb:

Robert
 
#123 ·
Time for a little update.

I thought the 17 was sorted out, but it turns out that the heavy bolt handle that Robert gave me, has began to crack. I was going to make a heavier handle, because the cases were still bulged, but far less than before the heavy handle. After taking it apart, I saw the heavy handle was cracked right where the arm goes over the bolt, not at the handle itself. This is a major bummer. Since the modified handle weighed 60 grams (the stock handle weighs 20 grams), making it heavier would only crack it faster.

The good news is that by using the heavy handle, I was able to get closer to figuring out what the rifle needs. The bad news is that I need to add at least 40 grams to the bolt assembly, and there aren't too many good ways to do it.

One idea we came up with was to slot the receiver on the opposite side of the handle, and bolt some Mallory to that side of the bolt. The Mallory could be disguised to look like a ambidextrous charging handle. The only thing that concerns me with doing that is... if it goes kaboom, debris/shrapnel will be more likely to hit me in the face. But I could build a guard to cover the opening.

Here is a pic of the crack, sorry, crappy cell phone pic.



Here is a pic of where the bolt will be tapped, if I decide to go that route. Also, if I bolt a piece of Mallory to the bolt, the bolt will be notched .010-.020", so the new handle will fit tight and won't be able to move forward or backward, and the bolts holding it on will just keep the handle pulled tight to the bolt. Btw, the word bolt is used in a few different context's here, lol.

 
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