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View Full Version : My AK hates the Spike's Dynacomp.Help needed.


bighead
10-13-2012, 4:47 PM
Greetings,

So last week I decided to try a new brake for my Arsenal AK(7.62x39).I found it on sale here...

http://www.outdoorgearbarn.com/p-39928-spikes-tactical-ak-dynacomp-muzzle-brake-762x39-caliber-24x15-rh-thread.aspx

I spun it on last nite and headed to the range with a friend who has the same exact rifle and newly added Dynacomp.I started at the bench shooting out to approx 200 yds to punch steel that my Arsenal normally hits with relative ease.I instantly noticed that my shots were landing 2 feet to the right every single time.

I wondered if my optic had lost zero so I checked to see if the mounts were loose and they were on rock solid.At this point I asked my friend next to me if his was doing the same thing and he showed me it wasn't.I then figure I would try having the brake sit higher or lower on the thread.Same result, shots were landing every time 2 feet left.I then decided to take the comp off and shoot it brakeless.It instantly returned to zero and normal precision/accuracy.

I then decided to try my friend's comp who was having zero issues with his.Same thing, more shots 2 feet to the right.At this point I concluded my gun hates this thing and finished the day without the brake on.I checked the threads on both the comp and barrel and saw nothing peculiar.I would love to keep the Dynacomp because it had a noticable effect on recoil and bettered my follow up shots.

At this point Im not sure wether to send it back for a refund or ask for an exchange.I'm mechanically retarded so I offer this up for any advice from the experts on this board.

I did notice there was some scoring on the port of the brake after I looked at the pictures.I have no clue what would cause this.


http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0287_zps93492399.jpg

http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0288_zpsa5387b5c.jpg

http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0289_zpsc052d707.jpg

Notice the slight scoring on the port below

http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0290_zps831e6907.jpg

Same here

http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0291_zpseb91aaca.jpg

http://i419.photobucket.com/albums/pp273/ilovejiujitsu/DSC_0292_zps7d66d629.jpg

Sorry for the long winded thread, any help is greatly appreciated.

21SF
10-13-2012, 4:50 PM
It can change the point of impact, any brake can. Why didn't you re-zero?

mrvash
10-13-2012, 6:10 PM
It can change the point of impact, any brake can. Why didn't you re-zero?

^This

CSACANNONEER
10-13-2012, 6:19 PM
Rezero and see how well it shoots. You may find that it shoots more precise with it than without it.

CHS
10-13-2012, 6:28 PM
ANY muzzle device has the ability to change the point of impact. That's all that has happened and nothing more.

Just re-zero and you're done.

Inquirer
10-13-2012, 6:41 PM
The threading of the item you linked is 24x1.5 RH. Isn't the typical threading of the AK 14x1 LH?

Revolver Ocelot
10-13-2012, 6:59 PM
The threading of the item you linked is 24x1.5 RH. Isn't the typical threading of the AK 14x1 LH?

Did you look at the pics of his gun? It yes the 24x1.5 threaded sight block.

Cadre
10-13-2012, 7:31 PM
I did my rezero no problems with mine.

LOW2000
10-13-2012, 7:55 PM
That scoring looks like you're getting some strikes on the end of the comp, like the threads aren't quite concentric to the bore. Not a big deal with a short break or with something that has a large exit hole, but you're obviously having some issues. May want to bore out the exit to be a little oversize and see if that cures the problem. It could just be that the comp throws off POI however since it did the same thing when threaded on your buddy's gun. Many suppressors have the same issue of POI shift. If it is repeatable, then just rezero.

joelukehart
10-14-2012, 1:36 AM
Did you swap the the FSB. It looks seriously beat up. Like someone pounded the muzzle on the ground. I bet whoever put it on beat home with a hammer.

tujungatoes
10-14-2012, 8:23 AM
Did you swap the the FSB. It looks seriously beat up. Like someone pounded the muzzle on the ground. I bet whoever put it on beat home with a hammer.

That looks to be built up carbon fouling Which might also be changing the POI since it's built up all over the crown. Clean all that carbon fouling off the muzzle and it might shoot a little better.

Speedpower
10-14-2012, 8:38 AM
Greetings,

So last week I decided to try a new brake for my Arsenal AK(7.62x39).I found it on sale here...

http://www.outdoorgearbarn.com/p-39928-spikes-tactical-ak-dynacomp-muzzle-brake-762x39-caliber-24x15-rh-thread.aspx

I spun it on last nite and headed to the range with a friend who has the same exact rifle and newly added Dynacomp.I started at the bench shooting out to approx 200 yds to punch steel that my Arsenal normally hits with relative ease.I instantly noticed that my shots were landing 2 feet to the right every single time.

I wondered if my optic had lost zero so I checked to see if the mounts were loose and they were on rock solid.At this point I asked my friend next to me if his was doing the same thing and he showed me it wasn't.I then figure I would try having the brake sit higher or lower on the thread.Same result, shots were landing every time 2 feet left.I then decided to take the comp off and shoot it brakeless.It instantly returned to zero and normal precision/accuracy.

I then decided to try my friend's comp who was having zero issues with his.Same thing, more shots 2 feet to the right.At this point I concluded my gun hates this thing and finished the day without the brake on.I checked the threads on both the comp and barrel and saw nothing peculiar.I would love to keep the Dynacomp because it had a noticable effect on recoil and bettered my follow up shots.

At this point Im not sure wether to send it back for a refund or ask for an exchange.I'm mechanically retarded so I offer this up for any advice from the experts on this board.

I did notice there was some scoring on the port of the brake after I looked at the pictures.I have no clue what would cause this.


Sorry for the long winded thread, any help is greatly appreciated.

That's a funny comment their, what is the use of better follow up shots if you can't hit the target?

BucDan
10-14-2012, 8:45 AM
That's a lot of carbon buildup! So much that it looks like mold.

bighead
10-14-2012, 8:45 AM
Thank you guys for your help, I really appreciate it.I will clean the crown up and re-zero.

uxo2
10-14-2012, 6:44 PM
Do you ever clean that thing

zfields
10-14-2012, 6:48 PM
Do you ever clean that thing

AK = Cleaning optional.

chead
10-14-2012, 7:55 PM
At the very least clean the crown if you're shooting for groups. It makes a difference.

bigbob76
10-14-2012, 8:30 PM
At the very least clean the crown if you're shooting for groups. It makes a difference.

When I saw all that crud I thought it was a joke by the OP so I didn't comment on it. I'm guilty of getting my guns good and dirty before cleaning. If I was going to do any shooting for comparison I would definitely do some basic cleaning.

bighead
10-14-2012, 9:20 PM
Update, went to range today, cleaned the crown thoroughly and attempted to re-zero.I chased the poi all over the place from the bench.I then noticed the comp was loose to the point of tilting slightly from it's axis.Im pretty much ready to send it for an exchange.I could be wrong but my conclusion is the bullet is nicking the port of the brake.Like I said im mechanically handicapped so I appreciate all the suggestions.

chead
10-14-2012, 10:35 PM
Tilting laterally relative to the bore? That's not normal, but if a bullet hit it, I doubt it would wind up on the paper at all and might launch the comp. Spinning a bit on the threads is normal and okay.

Grumpyoldretiredcop
10-14-2012, 11:08 PM
You may want to check whether your bore and brake are concentric before you start hogging out your brake or sending it back. I'd try a solid rod at roughly bore diameter - see if you have a cleaning rod that's close for a quick and dirty check. If the rod touches or nearly touches the brake exit, or if smaller than bore diameter, clearly doesn't pass through the center of the brake exit, that may be your issue. Your AK wouldn't be the first one with an FSB that's not aligned with or concentric to the bore.

bighead
10-14-2012, 11:09 PM
Tilting laterally relative to the bore? That's not normal, but if a bullet hit it, I doubt it would wind up on the paper at all and might launch the comp. Spinning a bit on the threads is normal and okay.

Yes, tilting relative to the bore.Looking down on it from the top I can wiggle it left to right.I tightened it as far as it would go also and it still "wiggles."

bighead
10-14-2012, 11:11 PM
Tilting laterally relative to the bore? That's not normal, but if a bullet hit it, I doubt it would wind up on the paper at all and might launch the comp. Spinning a bit on the threads is normal and okay.

You may want to check whether your bore and brake are concentric before you start hogging out your brake or sending it back. I'd try a solid rod at roughly bore diameter - see if you have a cleaning rod that's close for a quick and dirty check. If the rod touches or nearly touches the brake exit, or if smaller than bore diameter, clearly doesn't pass through the center of the brake exit, that may be your issue. Your AK wouldn't be the first one with an FSB that's not aligned with or concentric to the bore.

Grumpy I didn't think of that, good idea.

21SF
10-15-2012, 9:28 AM
Update, went to range today, cleaned the crown thoroughly and attempted to re-zero.I chased the poi all over the place from the bench.I then noticed the comp was loose to the point of tilting slightly from it's axis.Im pretty much ready to send it for an exchange.I could be wrong but my conclusion is the bullet is nicking the port of the brake.Like I said im mechanically handicapped so I appreciate all the suggestions.

Yes, tilting relative to the bore.Looking down on it from the top I can wiggle it left to right.I tightened it as far as it would go also and it still "wiggles."

What are you tightening it with? By hand?

Use a wrench on the flats and some locktite.

zfields
10-15-2012, 9:34 AM
What are you tightening it with? By hand?

Use a wrench on the flats and some locktite.

Most AK's you don't loctite, since you need to remove them often to clean for corrosive ammo.

bigbob76
10-15-2012, 9:38 AM
I thought this was pinned and welded, how can it be tightened?

Cadre
10-15-2012, 10:47 AM
mine was a little tight i had about 1/8 of an inch before the next slot with some force it goes in but i can see it tilting down. i filed the brake on both sides of the slot fits good now.

http://i1037.photobucket.com/albums/a458/seronian/DSC_0292_zps7d66d629k_zpsab40eede.jpg

chead
10-15-2012, 10:56 AM
Most AK's you don't loctite, since you need to remove them often to clean for corrosive ammo.

And don't tighten except by hand. If you use a tool I promise you will regret it and possibly damage your sight block. :(

HK Dave
10-15-2012, 11:01 AM
Just like most people have said, installing a brake can change your POI and requires a re zero.

Also, the crown of your barrel is caked... that's gotta be hurting accuracy.

bighead
10-15-2012, 11:17 AM
Crown has been cleaned and I tightened it by hand, still loose to the point of shaking the front of the rifle causes a rattling noise.

bighead
10-15-2012, 2:42 PM
I emailed outdoorgearbarn and they said it sounds defective, Im returning it for an axchange.

Thunder Beast
10-15-2012, 3:56 PM
Let us know how it goes, I'm interested in purchasing one.

starsnuffer
10-15-2012, 4:05 PM
If you're shooting from a bench, a brake isn't going to get you anything but more noise. I'd just send it back and return to normal.

-W

killshot44
10-15-2012, 8:24 PM
You said it did the same thing with your friend's comp, correct?

It sure sounds like the barrel threads are not cut concentric to the bore.
If so, it doesn't matter what you screw on there - you'll still have this problem.
Get to a 'smith that can recut the barrel threads.

ZX-10R
10-16-2012, 7:21 AM
AK = Cleaning optional.

+1.

bighead
10-16-2012, 10:49 AM
When I tried my friend's identical comp the poi was consistently right, this is understandable.On mine, the bullet was grazing the port on the comp.Im returning the old for a new and as long as I dont get scoring marks on the port Ill rezero and post a report, if not Im going back to the old 74 brake.

CHS
10-17-2012, 3:22 PM
AK = Cleaning optional.

Really? I've got all this great corrosive ammo that disagrees with your assessment.

chead
05-26-2013, 4:51 PM
Bumping this ancient thread to report I just found what looks like scoring from a strike on my AK Dynacomp, but this one's in 7.62x39..

TheExiled
05-26-2013, 6:28 PM
I recall at least one more thread reporting the same a while back.. seems to be more common than I would like. Seems like the best bet would be to find a dowel or rod the diameter of the bore and see if it rubs the comp

peppermintman
05-26-2013, 6:41 PM
Yes, tilting relative to the bore.Looking down on it from the top I can wiggle it left to right.I tightened it as far as it would go also and it still "wiggles."

How about t he crush washer thingy? With one of those it ought to tighten up lots.

MrPlink
05-26-2013, 6:56 PM
Bumping this ancient thread to report I just found what looks like scoring from a strike on my AK Dynacomp, but this one's in 7.62x39..

well just about every possible issue has been hashed on on this thread, what do you think is causing yours?

chead
05-26-2013, 7:00 PM
well just about every possible issue has been hashed on on this thread, what do you think is causing yours?

I can't get it tightened all the way down to the last thread so it wiggles JUST enough that a bullet clipped. I assume it just needs a shim. I tried it on two AKs and it doesn't bottom out the threads on either. Not sure what AK Spike's used for reference, but putting a washer on should do the trick.

peppermintman
05-26-2013, 7:29 PM
I can't get it tightened all the way down to the last thread so it wiggles JUST enough that a bullet clipped. I assume it just needs a shim. I tried it on two AKs and it doesn't bottom out the threads on either. Not sure what AK Spike's used for reference, but putting a washer on should do the trick.

Did a little surfing and came up with this....
http://www.cheaperthandirt.com/product/2-SPKSBV1019

There's diffenitly a crush washer included so I need ask.....you have crush washer installed too????:iagree:


I just installed 2 compensators :43: and both came with a crush washer :)

chead
05-26-2013, 7:52 PM
Mine didn't come with a crush washer, I didn't think any of hte AK variants did?

MrPlink
05-26-2013, 7:57 PM
There's diffenitly a crush washer included so I need ask.....you have crush washer installed too????:iagree:


Mine didn't come with a crush washer, I didn't think any of hte AK variants did?

I would guess that the crush washers are for the AR (well, non AK anyways) models as well. Might want to contact SPIKES either way

peppermintman
05-26-2013, 9:18 PM
Mine didn't come with a crush washer, I didn't think any of hte AK variants did?

Yeah I think you right. I took a closer look and all I saw were those clocking slots on it for the pin? Their website showed some close ups of the comp but it was on a pistol. My slant has a little wobble but never had a problem with it. Could mean more range time or maybe he really got a bad one, who knows.

BucDan
05-27-2013, 4:43 PM
I was looking to get the spikes dynacomp for the 7.62 also, but the striking will worry me a lot. I see that using a washer will help, but I'll wait it out a bit.

bighead
05-28-2013, 10:11 PM
Mine didnt come with a crush washer either.

bighead
05-28-2013, 10:15 PM
Nor did the re0lacement comp include a crush washer.