New Build Grendel Benchrest Bolt Action for 100yd & 200yd

[watrob]

Decided to build a sister comp rifle to the one in the foreground of the attached photo. The one shown is in 22 PPC, handmade carbon fibre stock, Pearce Action, 24" Krieger SS Barrel, Jewell Trigger and March Scope.

The Grendel will have a 26" Krieger barrel, have had the reamer modified for a tighter neck & longer throat.

The photo of the cartridge is a Norma 100gr BTHP Match grade bullet giving me OAL of 2.320". This leaves room for powder to up to the case shoulder and we hope around 3000fps to 3150fps.

[JASmith]

That looks like a neat project!

While getting 3,000 to 3150 fps with a 100 grain bullet from the Grendel case will be truly impressive, is there a competive advantage to that velocity versus, say, 2900 fps?

[lrgrendel]

So this brings up a question.

Is Saami spec regarding pressure in the 6.5 Grendel based on an AR style of chamber as this round was developed around this platform or is a chamber a chamber.

I guess what I am really asking is, is the max Saami pressure the same for a bolt gun as what was developed in the AR???

[JASmith]

The SAAMI pressure is a guideline for ammunition manufacturers, so is independent of the acition.

SAAMI also defines a proof load pressure to be sure of cinfirming that a particular firearm is safe.

What bothers me is that some folks think that they have a chance of getting Creemoor-like velocities from the Grendel. The Creedmoor runs at pressures that are almost 20 per cent higher and has more than 40% greater case volume.

The Grendel is a fine cartridge and very effective in many areas. The larger cartridges with greater case volume running at higher pressures will get faster velocities. The price paid to the extra speed is more recoil and usually larger, heavier rifles.

[sneaky one]

As JASmith and I have found- the only way to up the speed of the Grendel is to use lighter bullets. Von Gruff, went the other direction- he had a chamber reamer made to his specs- the Grendel Max., for his boltie.

He sent me a few retired cases to inspect.,,, it can be done in an AR. But will require some custom bullet work to gain the maximum. I could do some in small batches.

It's closer to 6.5 x 55 Swede speeds.

I took my deer last fall with a 77 grn. GMX pill traveling 2974 fps. from a 16" tube,--- 3074 from my Entry 20" tube. BTW- 26 " of penetration thru the Rambo Muscle mass, then thru the spinal column- rib bones- heart lung liver , it was amazing from 20 yds. This is how I enhanced the Grendel. 280 live wt.

ALSO, How the 6.5 Swede got its reputation, Ask Bob Stokes- Its the middie caliber that shows the best results.

He is the Grand Slam Guy in USA.

[kmon]

Loading the Grendel up to higher pressures in strong bolt action rifles has been discussed before and some do it. I thought about loading hotter for the bolt action than the 52k max listed but don't do it because that IMO is not what the Grendel is about IMO. The little Grendel is a great balanced cartridge with great accuracy potential, low recoil, low muzzle blast yet with plenty of reach with enough energy delivered on target to cleanly take game further than most should be shooting at game.

Loading the Grendel hot as in 58-60K can be done in a strong bolt action but at the expense of shortened case life, shortened barrel life with more recoil and muzzle blast. I thought about loading up the Grendel to higher pressures last year but decided it is not needed and if I want more performance out of a 6.5 caliber round then I will just get the 6.5-284 or 264 Win Mag from the safe.

By the way that is a great looking stick in the picture.

[watrob]

We load hot our 6mm PPC rounds in benchrest all the time, our FL bump dies are chamber matched and flattened primers are the norm, I also Boron coat my bullets as well as the barrel. Attached photo is load development, 3 shoot group at 100yds.

[JASmith]

There may be some wisdom in keeping your loads in the private message channel.

It is too easy for one of us to confuse a custom hot load for a run of the mill "max" load and be surprised when the primers, brass, bolt and other things complain.

[watrob]

Our loads would certainly destroy a AR rifle action fairly quickly, this Grendel build will be interesting, velocity is not far behind the BR case and will have good accuracy at 200 yards. 30 BR at 200yds does have its problems, its recoil is a killer by the end of the day's shoot and its groups not as good hence it's used in Hunter Class for scoring. In group shooting at 200 yards the 6 PPC is running out of steam and wind effected, so with nearly 4 grains of extra powder in a Grendel case and heavier bullets to buck the wind it will make it an interest experiment.

[JASmith]

What bullets are you running in the 6 PPC?

[watrob]

The go to projectile was the Berger 64.**gr Column and also the 68 gr Berger's but you need a higher twist to shoot heavy projectiles and once you go a heavier bullet with a higher twist in a 6 PPC the cartridge does not hold enough powder so the Grendel cartridge will be interesting. One record stands at the moment of Grendel necked up from 6.5mm to 30 shooting a group of 0.007" at 100 yards, so it will shoot.

[JASmith]

Have you looked at the 6 BR Norma or its 6.5 mm counterpart?

You should be able to get the velocities you like with them and the popular literature suggests they too have a reputation for good accuracy.

[pds]

I shoot benchrest, until someone makes 85-100 gr benchrest quality 6.5 dia bullet the Grendel will never compete with the 6ppc in a BR match. Get a handmade bullet made with quality uniform jackets and it would be interesting to see. I see no real advantage at 100 yd however at 200 yd under windy conditions it should have an advantage but recoil is also a big issue with BR shooting.

PDS

[watrob]

I shoot benchrest, until someone makes 85-100 gr benchrest quality 6.5 dia bullet the Grendel will never compete with the 6ppc in a BR match. Get a handmade bullet made with quality uniform jackets and it would be interesting to see. I see no real advantage at 100 yd however at 200 yd under windy conditions it should have an advantage but recoil is also a big issue with BR shooting.

PDS

The 6.5mm 100 gr Norma is a match grade target bullet "Banskytte/Rekrutt HP 6,5 g/100 gr - Product #20665091", its just hard to get hold of. They make a Hunter bullet in the same design so some people get confused.

https://www.norma.cc/en/Products/Components/Match-Bullets/

[qviking]

What twist rate did you decide to use? My best friend and I are gathering components for a very similar build.