[TronJohn]

Please respond with unbiased opinions.

For those that have seen examples of both, overall, which refinish looks better, and secondly, which seems to be more durable?

IGF or RDTS?

I'm not sure if it makes a difference or not, but it will be on an 53.

(As of yesterday I was ready to buy a clone, but now as of today I think I might just save an extra $1000 and wait until I can find a HK93 to have cut down so I can have bragging rights of having a real Lamborghini.)

If using a real HK93, what additional parts are still needed to either add-on or replace existing parts in order to make it a brand new HK53?

(The only thing that really draws me to RDTS, even though I think they are more expensive over IGF is that they make their cans out of steel, which seems to me would make them last a lifetime, whereas aluminum can dent easily. I plan to make this a SD version, so that's why this applies to me.)

 

[hkinak]

parts needed

53 barrel
53 cocking tube and cocking lever
53 carrier and locking piece
53 recoil rod and spring
53 buttstock with buffer

I think the rest can be recycled from the 93. As far as who to have do the work, well I own rifles built by IGF, RDTS, and Urbach. I would say all of them do very high quality work and you would not be dissapointed. Since the 53 was a factory design, all parts are standardized and you don't have to worry about any exotic or proprietary design like the 51, 51K or 53K. As far as making a 53SD, you can work with a number of superssor manufacturers in coming up with a supressor for the rifle. AS far as I know, IGF does not make supressors. I would talk with experts in the supressor game like SRT arms, or Gemtech to see if they have a version that can be used in a 53SD and then RDTS or IGF can make it part of the gun.

I hope this helps and I know that you will get a quality product no matter who you choose.

 

[TronJohn]

Thanks.

Aren't they able to just cut the barrel down? I know this can be a larger cost if going with a german barrel.

Do you happen to know a price range on the other parts by chance?

By adding on a real supressor, how much velocity, penetration and punch am I going to lose?

 

[hkinak]

You can get away with cutting down the 93 barrel, but if you are going to the extent of building a 53SD, I would maybe choose a new 53 kit with a 53 barrel so you can get a better twist rate than the old 93 barrels. Also, I would that ballistic performance will only suffer marginally since youare already going out a short barrel (53's are 8.5 inch barrels)... One thing I do not know is how much further the 53 SD barrel is cut down.

Price of the parts........I just paid $625 for a brand new factory 53 complete bolt and carrier assembly. check with Adam at

http://www.hkparts.net/index.htm

 

[csbrit007]

As far as the build is concerned I would speak with each smith on how they will modify your existing 93 or a 53 parts kit you may consider purchasing to work as either one will have to be modified to work in SD form if they even offer that kind of conversion.

Also just to add to what hkinak was saying about the 53 having a better twist rate some 93's also came with a 1/7 twist barrel while not as common you can still find one for sale from time to time. For instance there is one for sale right now in the HK firearms for sale board for $2500. Link: http://hkpro.com/forum/showthread.php?t=67578

 

[TronJohn]

What is considered a "good twist rate" for a short barrel like on a 53?

 

[hkinak]

The best twist rate for the 53 is the 1/7 which will allow shooting up to 82 gr bullets, but then you need a different locking piece. For your SD, you will want to get a special locking piece for hard to find subsonic ammo. I would check with some of the big class 3 dealers to see if they have any factory HK 53 police trade-ins that can be cut up for a parts kit. Louis at Southwest Tactical, or Ruben Mendiola both are great dealers and are very helpful.

 

[darthvictor]

Subsonic 5.56? Isn't that called .22lr?

Never heard of such a thing.

 

[MONEY]

Most people I have talked with said the Hk53 would probably have baffle strikes & was not a good idea to try to supress a .223 with that short of a barrel.

 

[TronJohn]

According to Jayson at IGF, the velocity of a .22 lr is 1000 fps where as a .223 is 3000 fps and adding a suppressor onto it does not reduce the velocity.

If you have an integral suppressor with a ported barrel, then that would reduce the velocity, but those aren't used on .223's.

He also said that .223 uses a standard screw on suppressor.

What exactly are baffle strikes? How would a suppressor be applied without having baffle strikes?

Hkinak - Am I looking just for a special locking piece for hard to find subsonic ammo?

Or am I also looking to use hard-to-find subsonic ammo as well?

What other kinds of .223 ammo are there other than subsonic? What would be the benefits in going with a subsonic ammunition?

What grains are normally shot in .223? Is 82 grain the highest?

 

[withoutremorse42]

u

RDTS does great work. My experience with them was very positive and my work was done quickly. However another member of this site and a friend of his both had issues with the customer service. YMMV

Baffle strikes are when the bullet dings (or worse) the inside of the suppressor. I'm no expert but I believe having bad ammo/barrel twist combinations (bullet yawing) is a major cause of this.

As for supersonic/subsonic you have a couple options.

If you use regular supersonic ammo I dont think you will need to switch out the locking piece (unless the different barrel length factors) and you will find shooting with the suppressor much more comfortable, but not nearly as quiet as if you used subsonic ammo. The initial "crack" is dampened but the sonic boom still makes plenty of noise downrange. In the military we used supersonic ammo/suppressor combo's often as it helped protect our hearing and enhanced team communication.

Subsonic ammo will require a new locking peice and as stated above, will be much quieter all around but at greatly reduced bullet velocity and as such, a much "rounder" trajectory curve.

Hope this helps.

 

[TronJohn]

So if I stick with a 1/7 barrel twist and high quality supersonic ammo, I should not have problems with baffle strikes?

Well I would like to keep the velocity as high as possible, so I would probably stick with supersonic.

What is the difference between a supersonic and a subsonic bullet? The grain amount?

What grains does supersonic ammo come in? Obviously the higher grain, the more velocity & punch the bullet will have?

How well will supersonic, high grain ammo shoot in full auto through a well milled suppressor?

Are there more chances of having baffle strikes shooting in full auto with a supersonic round?

 

[hkinak]

I have used subsonic .223 ammo before and you must have a very well matched rilfe barrel /supressor to handle it. The benefit of subsonic ammo is that is stays under the speed of sound throughout it trajectory, and therefore you do not hear the bullet "crack" or "snap". Supersonic, or standard .223 comes in your typical 55, 62, 69, or 82 gr weight. Supersonic and subsonic bullets are usually the same design, it is just the powder load that changes the bullet characteristics.

If you stick with a 1/7 twist and use light grain ammo you should not have problems with baffle strikes or keyholing at the target. Now a supressor that you intend to you in a full auto is going to require some additional engineering. The supressor must be full auto rated, and even at that you can only shoot small bursts through it. You will need to make sure that the supressor is design so it will not overpressure and blow out on you.

In a 53SD, the barrel and supressor are intergrated to create a barrel overall length of about 8.5 inches. Considering the dynamics of the short barrel and the supressor, proper matching and milling is without question.

Hope that helps.

 

[TronJohn]

Yes, you have helped very much & I am learning a lot.

So if the design of the bullet is the same between supersonic & subsonic, then the only thing that separates them is the grain weight? If so, I would assume that subsonic rounds are rated 55gr & lower then?

Would having the suppressor made out of steel over aluminum give me better chances of not having a blow-out and over-pressuring when in full auto?

What barrel twist would be appropriate to use grains all the way up to 82gr?

Does 1/7 mean that it is a smaller/tighter twist than 1/12? If so, then the smaller the twist, the tighter the bullet will be held, keeping it in place longer, making it go straighter over longer distances without key-holeing? Am I understanding this correctly?

Is it a bad idea to think that one can run 82gr supersonic in full auto in more than just short bursts?

There must be suppressors on the market that are able to be run in complete full auto isn't there? Can something of this nature be milled out of steel?

 

[TronJohn]

I have been doing a little bit of research on suppressors as I am new to them as well.

And quite quickly I stumbled upon Reflex suppressors.

http://www.canadiantactical.ca/technical.html

They make the claim as follows...

Supersonic Automatic Fire

High rates of fully automatic fire are the most difficult challenge for any suppressor. Excessive heat and pressure can both destroy the suppressor tube and baffles as well as the host rifle's barrel. The Reflex Suppressor is specifically designed and built to survive almost unlimited amounts of automatic fire. It is one of the only suppressors certified for use on belt fed weapons.

Is anyone familiar with these?

Obviously I would need to have a special suppressor manufactured since I am building a custom gun, but could they then engineer a suppressor based on a company's design such as Reflex, if in fact they do stand up to full auto fire?

 

[TronJohn]

Anyone?

 

[hkinak]

I have never heard of them and from the e-mail address they are a Canadian company so I would have to check with them on ATF rules for importation.

the material the superssor is made out of does have some bearing on its strength, howerver, the baffle design is more important. There are full auto supressors out there, but they are more engineered for the gun than the round it fires. The baffles are engineered for the cyclic rate of the firearm as the pressure wave inside the baffles can be lowered based on it design, then all you have worry about about is heat and expansion of the baffles. To counter the heat buildup some baffles are convex design so their heat stretch is lowered to reduce the possibility of a baffle strick due to heat.

As far as the barrel, the lower the number the faster the twist. Basically 1/7 means that the bullet will complete one rotation in 7 inches of barrel travel, while a 1/9 means a bullet will complete one rotation in 9 inches of travel. The faster the twist, the better stability; however, you can over twist a bullet and make it have too much centripetal force that it basically will key hole once it leaves the barrel. Most ballistics have a sweet twist rate based on the round. 55 gr is a 1/9 or even 1/12, while 82 gr is 1/7, in 223, that changes significantly with caliber of the bullet; a 308 sweet twist is about 1/11 for a 165 gr bullet.

I would really recommend that you sit down and talk with the guys at SRT Arms or Gemtech. These guys are tops in the supressor market and know more than anybody about what it takes for any job.

 

[AviatorDave]

hkinak - kudos for correct usage of centripetal force.

 

[TronJohn]

I have been emailing Jayson back and forth from IGF and he has been really helpful and super nice.

He said that he would machine the suppressor himself so that there is no chance of baffle strikes. He also said he would mill it out of steel or stainless steel. (what material would be a better choice, & for what reason?)

I would assume he has enough knowledge & experience to mill a proper suppressor that will do the job? ( I emailed him again tonight to see if he is also able to make the suppressor able to handle full auto, which I would think he could if he makes good suppressors.)

As far as the twist rate, Cohaire arms has said this about their barrels...

we got NEW hk 33 kits as donors for the guns and will be USING Factory NEW Hk barrels yes hammer forged COrrect twist 53 barrels in our guns

So I guess the question is, what is the correct twist rate of factory HK barrels? 1/12 or 1/9? But weren't they putting 1/7 twist in their barrels at some point?

I may opt to sell the HK barrel and buy an american made 1/7 twist so I am able to shoot higher grain ammo.

 

[AviatorDave]

I have been emailing Jayson back and forth from IGF and he has been really helpful and super nice.

He said that he would machine the suppressor himself so that there is no chance of baffle strikes. He also said he would mill it out of steel or stainless steel. (what material would be a better choice, & for what reason?)

I would assume he has enough knowledge & experience to mill a proper suppressor that will do the job? ( I emailed him again tonight to see if he is also able to make the suppressor able to handle full auto, which I would think he could if he makes good suppressors.)

As far as the twist rate, Cohaire arms has said this about their barrels...

we got NEW hk 33 kits as donors for the guns and will be USING Factory NEW Hk barrels yes hammer forged COrrect twist 53 barrels in our guns

So I guess the question is, what is the correct twist rate of factory HK barrels? 1/12 or 1/9? But weren't they putting 1/7 twist in their barrels at some point?

I may opt to sell the HK barrel and buy an american made 1/7 twist so I am able to shoot higher grain ammo.

Stainless steel would be the toughest non-exotic material. There are other materials which are even better in high heat applications, like inconel, but you probably wouldn't be interested in a $3,000 suppressor.

But as for the twist rate - they could be either 1/12 or 1/7. My guess is that they'll probably be older 1/12 barrels, because the 1/7 barrels themselves have a much higher value and I believe it would add too much to the price of the gun. I think the 1/7" barrels were introduced around 1988 or 89. I know some still claim there are 1/7 barrels that are not marked as such with the 178 stamp, but I've still never personally seen one. Until I do, I'll assume that if it doesn't have 178 stamped on it, it's a 1/12 twist barrel.